1. The document discusses the characteristics and operation of sensors within a smartphone. It describes the multiple conversion steps that occur as a stimulus is converted to an electrical signal, using a pressure-detecting optical fiber sensor as an example.
2. Key concepts in sensor characterization are introduced, including the transfer function describing the output-input relationship, span/full scale input and output, accuracy, calibration error, hysteresis, nonlinearity, resolution, selectivity, and sensitivity. Ambient conditions that can influence sensor operation are also noted.
3. Fundamental electrical and materials concepts are reviewed, such as electric charges and fields, capacitance, dielectric properties, resistance, piezoelectric and moisture-sensitive effects that can be
1. The document discusses carrier transport mechanisms in semiconductors including drift, diffusion, and generation-recombination. It explains how mobility, resistivity, and the Einstein relationship relate these concepts.
2. Recombination and generation processes are defined as the annihilation or creation of electron-hole pairs. Various recombination mechanisms such as band-to-band, defect-assisted, and impact ionization are described.
3. Momentum considerations for different carrier transition processes like photon-assisted and phonon-assisted are discussed, noting that photons carry little momentum while phonons carry more momentum.
This document provides information about PN junction diodes and their characteristics:
1) It describes how a PN junction is formed by combining P-type and N-type semiconductors, forming a depletion region.
2) It explains the I-V characteristics of a diode under forward and reverse bias, including how the depletion region changes with bias.
3) Additional topics covered include drift and diffusion currents, temperature effects, capacitance effects, and recovery time characteristics important for switching applications. Special diodes like Zener diodes are also introduced.
The document provides information about bipolar junction transistors (BJT) and semiconductor diodes. It begins with definitions of key BJT and diode terms, such as drift current, diffusion current, depletion region, and diode current equation. It then discusses the structure and characteristics of PN junction diodes, including forward and reverse bias operation and their V-I characteristics. Applications of diodes are also listed. The document derives expressions for diffusion current density and the diode current equation. It explains diode switching characteristics like recovery time and examines the working and characteristics of PN junction diodes in detail.
1) Capacitance refers to an object's ability to store electrical charge. A capacitor consists of conducting plates separated by an insulator and is used to store electrical energy.
2) The capacitance of a parallel plate capacitor depends on the plate area, distance between plates, and the dielectric material between the plates - with larger areas, smaller distances, and higher-permittivity dielectrics increasing capacitance.
3) When a dielectric is placed in a capacitor, it polarizes under the electric field and reduces the overall field strength. This lowers the voltage needed to store a given charge, effectively increasing the capacitor's capacitance.
Electromagnetic Theory,coulombs law ,electric field intensity, electric flux density, charge distribution, gauss law, electric potential, relation between e & v, ampere's law, continuity equation, faraday law,Maxwell's law,biot savarat law,motional emf ,static emf ,numericals ,electromagnetic field ,voltage and emf relation ,divergence ,gradient.Application of Ampere’s law : Infinite Sheet Current
1. The document discusses conductors, dielectrics, current density, polarization, and electric susceptibility. It defines key concepts like current, current density, polarization field, dielectric constant, and boundary conditions for electric fields.
2. Conductors allow free electron flow while insulators have a large band gap; semiconductors have a small gap allowing electron excitation. Current density relates to charge velocity and conductivity.
3. Dielectrics have bound electric dipoles that contribute to polarization. The polarization field depends on dipole density and alignment with the electric field. Boundary conditions require continuous tangential E and normal D fields.
This document discusses electric, magnetic, and electromagnetic sensors and actuators. It begins by introducing capacitive sensors and actuators, which operate based on the principles of electric fields and capacitance. Capacitive proximity, position, and level sensors are described. The document then discusses magnetic sensors and actuators, which are based on static and time-varying magnetic fields. It provides an overview of magnetic theory, including permeability and the relationship between magnetic field intensity and flux density. Examples of capacitive and magnetic sensors and actuators are then presented.
The document discusses various types of sensors and transducers. It defines sensors as devices that measure physical quantities and produce a corresponding signal, while transducers are elements that experience a related change when subject to some input change. Common physical quantities that can be measured include temperature, pressure, light, current, and weight. Performance characteristics of sensors like range, error, accuracy, sensitivity, hysteresis, nonlinearity, repeatability, and resolution are also described. The document then discusses different types of displacement, position, velocity and motion sensors like potentiometers, strain gauges, capacitive, inductive, Hall effect, incremental encoders and tachogenerators.
1. The document discusses carrier transport mechanisms in semiconductors including drift, diffusion, and generation-recombination. It explains how mobility, resistivity, and the Einstein relationship relate these concepts.
2. Recombination and generation processes are defined as the annihilation or creation of electron-hole pairs. Various recombination mechanisms such as band-to-band, defect-assisted, and impact ionization are described.
3. Momentum considerations for different carrier transition processes like photon-assisted and phonon-assisted are discussed, noting that photons carry little momentum while phonons carry more momentum.
This document provides information about PN junction diodes and their characteristics:
1) It describes how a PN junction is formed by combining P-type and N-type semiconductors, forming a depletion region.
2) It explains the I-V characteristics of a diode under forward and reverse bias, including how the depletion region changes with bias.
3) Additional topics covered include drift and diffusion currents, temperature effects, capacitance effects, and recovery time characteristics important for switching applications. Special diodes like Zener diodes are also introduced.
The document provides information about bipolar junction transistors (BJT) and semiconductor diodes. It begins with definitions of key BJT and diode terms, such as drift current, diffusion current, depletion region, and diode current equation. It then discusses the structure and characteristics of PN junction diodes, including forward and reverse bias operation and their V-I characteristics. Applications of diodes are also listed. The document derives expressions for diffusion current density and the diode current equation. It explains diode switching characteristics like recovery time and examines the working and characteristics of PN junction diodes in detail.
1) Capacitance refers to an object's ability to store electrical charge. A capacitor consists of conducting plates separated by an insulator and is used to store electrical energy.
2) The capacitance of a parallel plate capacitor depends on the plate area, distance between plates, and the dielectric material between the plates - with larger areas, smaller distances, and higher-permittivity dielectrics increasing capacitance.
3) When a dielectric is placed in a capacitor, it polarizes under the electric field and reduces the overall field strength. This lowers the voltage needed to store a given charge, effectively increasing the capacitor's capacitance.
Electromagnetic Theory,coulombs law ,electric field intensity, electric flux density, charge distribution, gauss law, electric potential, relation between e & v, ampere's law, continuity equation, faraday law,Maxwell's law,biot savarat law,motional emf ,static emf ,numericals ,electromagnetic field ,voltage and emf relation ,divergence ,gradient.Application of Ampere’s law : Infinite Sheet Current
1. The document discusses conductors, dielectrics, current density, polarization, and electric susceptibility. It defines key concepts like current, current density, polarization field, dielectric constant, and boundary conditions for electric fields.
2. Conductors allow free electron flow while insulators have a large band gap; semiconductors have a small gap allowing electron excitation. Current density relates to charge velocity and conductivity.
3. Dielectrics have bound electric dipoles that contribute to polarization. The polarization field depends on dipole density and alignment with the electric field. Boundary conditions require continuous tangential E and normal D fields.
This document discusses electric, magnetic, and electromagnetic sensors and actuators. It begins by introducing capacitive sensors and actuators, which operate based on the principles of electric fields and capacitance. Capacitive proximity, position, and level sensors are described. The document then discusses magnetic sensors and actuators, which are based on static and time-varying magnetic fields. It provides an overview of magnetic theory, including permeability and the relationship between magnetic field intensity and flux density. Examples of capacitive and magnetic sensors and actuators are then presented.
The document discusses various types of sensors and transducers. It defines sensors as devices that measure physical quantities and produce a corresponding signal, while transducers are elements that experience a related change when subject to some input change. Common physical quantities that can be measured include temperature, pressure, light, current, and weight. Performance characteristics of sensors like range, error, accuracy, sensitivity, hysteresis, nonlinearity, repeatability, and resolution are also described. The document then discusses different types of displacement, position, velocity and motion sensors like potentiometers, strain gauges, capacitive, inductive, Hall effect, incremental encoders and tachogenerators.
This document provides an overview of electrical sensors and the physics principles they are based on. It discusses how capacitance, piezoelectric, and piezoresistive sensors work to detect phenomena by measuring changes in electrical properties like charge, fields, potential, capacitance, magnetism or inductance. Specific sensor types and examples are described, such as thermocouples, variable capacitors, water level sensors using capacitance changes, and piezoelectric sensors for traffic counting. The document reviews concepts of electrostatics, dielectrics, capacitance, and the piezoelectric and piezoresistive effects to explain sensor operation and characterization.
The document appears to be a student's lab report summarizing two physics experiments: (1) construction of a full wave rectifier circuit and (2) observing the diffraction pattern from a single slit. The report includes aims, apparatus, principles, diagrams, observations and results for each experiment. It also defines key components like the step-down transformer, p-n junction diode, capacitor and load resistance used in the full wave rectifier. For the diffraction experiment, it discusses concepts like diffraction, conditions for maxima and minima, and how the width of the central maxima varies with slit width and distance from the screen.
Here are some examples of FDA-approved therapeutic devices that use direct current (DC) electric fields:
- Bone growth stimulators - Use pulsed electromagnetic fields or capacitively coupled electric fields to promote bone healing of fractures that are not healing on their own.
- Transcutaneous electrical nerve stimulators (TENS) - Apply electric currents to stimulate nerves for pain relief and muscle rehabilitation.
- Iontophoresis devices - Use low-level electrical currents to drive ionized drug molecules through the skin for local drug delivery.
- Cardioversion/defibrillation devices - Apply controlled electric shocks to the heart to treat irregular heart rhythms like atrial fibrillation or ventricular fibrillation.
The document discusses electromagnetic theory, including Coulomb's law, electric field intensity, Gauss's law, electric flux density, electric potential, polarization in dielectrics, boundary conditions, Biot-Savart's law, Ampere's circuit law, magnetic flux density, Faraday's law, and motional EMF. Key topics covered include the relationship between electric and magnetic fields, conditions for electric and magnetic fields at boundaries between media, and how changing magnetic fields induce electromotive forces based on Faraday's law of induction.
Diploma i boee u 1 electrostatic and capacitanceRai University
- Static electricity is an imbalance of electric charges within a material that remains until the charge is able to move away through a current or discharge. It is contrasted with current electricity which flows through conductors.
- A capacitor is composed of two conductive plates separated by a non-conductive dielectric. It is used to store electric charge electrostatically and has applications in many electronic devices. The capacitance of a capacitor depends on the plate area, distance between plates, and the dielectric material.
- Electric flux is defined as the electric field strength multiplied by the area over which it acts. It represents the number of electric field lines passing through a surface and has units of volt-meters.
1. The document discusses various topics related to electrostatics including frictional electricity, properties of charges, Coulomb's law, units of charge, continuous charge distribution, electric field, electric field intensity, and the superposition principle.
2. It explains how rubbing certain materials like glass and silk generates static electricity through the transfer of electrons between the materials. Coulomb's law defines the electrostatic force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
3. Continuous charge distribution can be defined in terms of linear, surface, or volume charge densities. The electric field is the region of influence of a charged body on other charged particles
This document provides an introduction to the concept of electromagnetic fields. It begins by discussing electrostatics and defining electric fields as having their sources in electric charges. It then covers Coulomb's law, which describes the electric force between two charges, and Gauss's law, which relates the electric flux through a closed surface to the electric charge enclosed. The document explains electric field lines and flux, superposition of electric fields, and uses Gauss's law to analyze properties of conductors. Finally, it mentions that the next section will cover electric potential. The key information is that the document serves as an introduction to electromagnetic fields, covering fundamental concepts like Coulomb's and Gauss's laws.
current ,current density , Equation of continuityMuhammad Salman
1. Electric current in metallic conductors is carried by valence electrons, or free electrons, that move under the influence of an electric field. The velocity of these electrons is called the drift velocity.
2. Drift velocity is directly proportional to the electric field intensity and mobility of the electrons in the material. Higher conductivity materials like silver, copper and aluminum have higher electron mobilities.
3. The relationship between current density J and electric field E in a metallic conductor is defined by its conductivity σ, where J = σE. Conductivity depends on the charge density and mobility of electrons in the material.
This document discusses transmission lines and waveguides. It begins by defining key concepts like electrons, energy transfer through current and waves, and how the system used for energy transfer depends on frequency. It then covers topics like transmission lines, coaxial lines, parallel plate waveguides, various waveguide modes, and how circuit theory breaks down at high frequencies due to effects like skin effect. Filters and network analysis are also summarized. The document aims to provide an overview of guided communication systems ranging from circuits to optical fibers.
The document describes an electric field detector that uses ferrite material to detect electric fields over a volume, rather than just a surface area. It discusses how ferrite allows electric fields to penetrate its internal volume. The detector utilizes the microstructure and effects integration of an electric field over the volume of ferrite core. It provides advantages over previous detectors by reducing the effects of stray capacitance coupling and increasing sensitivity. Applications include detecting weak, medium, and strong electric fields from power lines and other energized conductors.
Experiment #{Experiment Title}Date Performed .docxrhetttrevannion
Experiment #
{Experiment Title}
Date Performed:
Date Report Submitted:
Report Author:
Lab Partner[s]:
Instructor’s Name:
Section Number:
I. Introduction
Three sentences are fine for the introduction. State what you measured, what you calculated, and what you are comparing your results to. Avoid using first person in the report. This section is 5 points. Refer to Appendix B and your Lab 1 Report for full instructions.
II. Data
This section is worth 20 points.
All measurements must be included and have proper unites and significant figures.
Data needs to be neat and understandable with explanations or equations.
Put in-lab data sheets signed behind this page when submitting the paper copy of your report.
The “data” heading can stay on the same page as the introduction or be hand written on top of the data sheet.
Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
III. Data Analysis
This section is worth 30 points. It contains the calculations, graphs, and sample calculations if one was performed repeatedly. Always calculate a percent difference between experimental and theoretical vales. There are directions on how to set up graphs in Appendix B.
You can use Word to type equations by clicking “Equation” on the “Insert” Tab or by clicking Alt and = simultaneously. Word lets you use Latex or Unicode to type equations. It also has buttons to press to insert symbols under the new “Design” tab if you do not know Latex or Unicode. If you hover over button, it will tell you how to type it using Latex or Unicode (whatever is selected)
The hypotenuse length can be found using the side lengths:
Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
IV. Discussion
This section will contain a table of summary results and paragraphs discussing the accuracy of results, the sources of errors, and the physics or answers to questions. Below is a sample summary table. Please be sure to update it or replace it with a table for the correct information.
Table 1 : Summary of Results
Measured Diameter [m]
Error in Measured
Theoretical Diameter [m]
%Difference
It is important to discuss types of error and largest error in your experiment. Refer to Section D of Appendix B and the Discussion from Lab 1 for more information.
V. Conclusion
You only need two sentences minimum and this section is worth 5 points. Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
2
Experiment 2
Electric Potential and Field Mapping
Introduction
In this experiment, you use a voltage probe and a computer data acquisition system to
measure the electric potential between two metal electrodes. The electrodes are placed in a tray,
which contains a shallow layer of water. The electrodes are connected to a D.C. power supply,
which maintains a constant potential difference. The water allows an electric current to flow
fr.
Experiment #{Experiment Title}Date Performed .docxnealwaters20034
Experiment #
{Experiment Title}
Date Performed:
Date Report Submitted:
Report Author:
Lab Partner[s]:
Instructor’s Name:
Section Number:
I. Introduction
Three sentences are fine for the introduction. State what you measured, what you calculated, and what you are comparing your results to. Avoid using first person in the report. This section is 5 points. Refer to Appendix B and your Lab 1 Report for full instructions.
II. Data
This section is worth 20 points.
All measurements must be included and have proper unites and significant figures.
Data needs to be neat and understandable with explanations or equations.
Put in-lab data sheets signed behind this page when submitting the paper copy of your report.
The “data” heading can stay on the same page as the introduction or be hand written on top of the data sheet.
Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
III. Data Analysis
This section is worth 30 points. It contains the calculations, graphs, and sample calculations if one was performed repeatedly. Always calculate a percent difference between experimental and theoretical vales. There are directions on how to set up graphs in Appendix B.
You can use Word to type equations by clicking “Equation” on the “Insert” Tab or by clicking Alt and = simultaneously. Word lets you use Latex or Unicode to type equations. It also has buttons to press to insert symbols under the new “Design” tab if you do not know Latex or Unicode. If you hover over button, it will tell you how to type it using Latex or Unicode (whatever is selected)
The hypotenuse length can be found using the side lengths:
Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
IV. Discussion
This section will contain a table of summary results and paragraphs discussing the accuracy of results, the sources of errors, and the physics or answers to questions. Below is a sample summary table. Please be sure to update it or replace it with a table for the correct information.
Table 1 : Summary of Results
Measured Diameter [m]
Error in Measured
Theoretical Diameter [m]
%Difference
It is important to discuss types of error and largest error in your experiment. Refer to Section D of Appendix B and the Discussion from Lab 1 for more information.
V. Conclusion
You only need two sentences minimum and this section is worth 5 points. Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
2
Experiment 2
Electric Potential and Field Mapping
Introduction
In this experiment, you use a voltage probe and a computer data acquisition system to
measure the electric potential between two metal electrodes. The electrodes are placed in a tray,
which contains a shallow layer of water. The electrodes are connected to a D.C. power supply,
which maintains a constant potential difference. The water allows an electric current to flow
fr.
1) An inductor opposes changes in current and stores energy in a magnetic field. A capacitor consists of conductors separated by an insulator and stores energy in an electric field. Inductors and capacitors are passive elements that can store but not generate energy.
2) The voltage across an inductor is proportional to the rate of change of current through it. The current through a capacitor is proportional to the rate of change of voltage across it.
3) Inductors and capacitors can be combined in series or parallel configurations, with equivalent inductance/capacitance values that are the sum/reciprocal sum of the individual components respectively.
This document provides an overview of transmission line modeling and analysis. It begins with assigning homework problems and then reviews electric field concepts such as Gauss's law and voltage difference calculations. Models for transmission line capacitance and inductance are developed considering both single and multi-conductor cases. Examples are provided to demonstrate how to calculate per phase capacitance, resistance, and inductance values for different conductor types using data from standard tables. Additional transmission line topics like multi-circuit lines, underground cables, and corona discharge are also briefly discussed.
This document provides a summary of key concepts in radio frequency (RF) acceleration for particle accelerators. It discusses early electrostatic accelerators like the Van de Graaff and their limitations. It then introduces the concept of RF acceleration using oscillating electric fields to continuously accelerate particles. Key RF acceleration techniques are summarized, including drift tube linear accelerators, cavity linacs, and the resonant TM010 mode used in most RF cavities. Important cavity concepts like the quality factor, resonant frequencies, and accelerating voltage are defined. Peak surface fields, power dissipation, and the equivalent circuit model of cavities including their shunt impedance are also covered at a high level.
The document discusses various mechanisms of charge carrier transport in semiconductors including drift and diffusion. It defines carrier drift as the movement of electrons and holes under the influence of an applied electric field. Carrier mobility is introduced as a material property that determines how fast carriers drift in response to an electric field. Diffusion is defined as the movement of carriers from areas of high concentration to low concentration due to random thermal motion. The Einstein relation links diffusion and mobility through the carrier temperature. Total current in a semiconductor is the sum of drift and diffusion currents.
This document provides an overview of electrostatics. It defines key concepts like electric field, electric flux density, Gauss's law, capacitance, and more. Applications of electrostatics include electric power transmission, X-ray machines, solid-state electronics, medical devices, industrial processes, and agriculture. Coulomb's law describes the electric force between point charges. Gauss's law relates the electric flux through a closed surface to the enclosed charge. Capacitance is the ratio of stored charge on conductors to the potential difference between them.
- Electrochemical impedance spectroscopy (EIS) measures the impedance of electrical circuits and chemical systems as a function of frequency. It provides more detailed information than DC techniques alone.
- Impedance replaces resistance as a more general parameter that accounts for frequency-dependent behavior of circuit elements like capacitors and inductors. It is defined as the ratio of voltage to current.
- EIS experiments involve applying a small AC potential over a range of frequencies and measuring the current response. The impedance is calculated from these measurements and plotted on Nyquist and Bode plots for analysis.
- Equivalent circuit models consisting of electrical components like resistors and capacitors are used to model electrochemical systems and interpret EIS data
The document summarizes an experiment on analyzing series and parallel RLC circuits. It describes:
1) Calculating the theoretical resonance frequency of a series RLC circuit as 18.8 kHz, but measuring it experimentally as 16.73 kHz, a difference of 11.1%.
2) Plotting the output voltage versus frequency, which reaches a minimum at the theoretical resonance point.
3) Analyzing the phase relationship and impedance characteristics at resonance, finding the voltage and current are in phase.
Hall generators and low resistance shunts are used to measure high direct currents. Hall generators use the Hall effect - when a current-carrying conductor is placed in a magnetic field, a voltage is produced perpendicular to the current and field. This voltage is proportional to the current. Low resistance shunts measure the small voltage drop across the shunt, which is proportional to the current.
Current transformers are used to measure high power alternating currents, as they provide electrical isolation. Electro-optical techniques transmit the voltage signal through an optical fiber to improve accuracy at high voltages.
Resistive shunts, magnetic probes, and Hall/Faraday effect devices are used for high frequency and impulse currents. Res
Implementing ELDs or Electronic Logging Devices is slowly but surely becoming the norm in fleet management. Why? Well, integrating ELDs and associated connected vehicle solutions like fleet tracking devices lets businesses and their in-house fleet managers reap several benefits. Check out the post below to learn more.
This document provides an overview of electrical sensors and the physics principles they are based on. It discusses how capacitance, piezoelectric, and piezoresistive sensors work to detect phenomena by measuring changes in electrical properties like charge, fields, potential, capacitance, magnetism or inductance. Specific sensor types and examples are described, such as thermocouples, variable capacitors, water level sensors using capacitance changes, and piezoelectric sensors for traffic counting. The document reviews concepts of electrostatics, dielectrics, capacitance, and the piezoelectric and piezoresistive effects to explain sensor operation and characterization.
The document appears to be a student's lab report summarizing two physics experiments: (1) construction of a full wave rectifier circuit and (2) observing the diffraction pattern from a single slit. The report includes aims, apparatus, principles, diagrams, observations and results for each experiment. It also defines key components like the step-down transformer, p-n junction diode, capacitor and load resistance used in the full wave rectifier. For the diffraction experiment, it discusses concepts like diffraction, conditions for maxima and minima, and how the width of the central maxima varies with slit width and distance from the screen.
Here are some examples of FDA-approved therapeutic devices that use direct current (DC) electric fields:
- Bone growth stimulators - Use pulsed electromagnetic fields or capacitively coupled electric fields to promote bone healing of fractures that are not healing on their own.
- Transcutaneous electrical nerve stimulators (TENS) - Apply electric currents to stimulate nerves for pain relief and muscle rehabilitation.
- Iontophoresis devices - Use low-level electrical currents to drive ionized drug molecules through the skin for local drug delivery.
- Cardioversion/defibrillation devices - Apply controlled electric shocks to the heart to treat irregular heart rhythms like atrial fibrillation or ventricular fibrillation.
The document discusses electromagnetic theory, including Coulomb's law, electric field intensity, Gauss's law, electric flux density, electric potential, polarization in dielectrics, boundary conditions, Biot-Savart's law, Ampere's circuit law, magnetic flux density, Faraday's law, and motional EMF. Key topics covered include the relationship between electric and magnetic fields, conditions for electric and magnetic fields at boundaries between media, and how changing magnetic fields induce electromotive forces based on Faraday's law of induction.
Diploma i boee u 1 electrostatic and capacitanceRai University
- Static electricity is an imbalance of electric charges within a material that remains until the charge is able to move away through a current or discharge. It is contrasted with current electricity which flows through conductors.
- A capacitor is composed of two conductive plates separated by a non-conductive dielectric. It is used to store electric charge electrostatically and has applications in many electronic devices. The capacitance of a capacitor depends on the plate area, distance between plates, and the dielectric material.
- Electric flux is defined as the electric field strength multiplied by the area over which it acts. It represents the number of electric field lines passing through a surface and has units of volt-meters.
1. The document discusses various topics related to electrostatics including frictional electricity, properties of charges, Coulomb's law, units of charge, continuous charge distribution, electric field, electric field intensity, and the superposition principle.
2. It explains how rubbing certain materials like glass and silk generates static electricity through the transfer of electrons between the materials. Coulomb's law defines the electrostatic force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
3. Continuous charge distribution can be defined in terms of linear, surface, or volume charge densities. The electric field is the region of influence of a charged body on other charged particles
This document provides an introduction to the concept of electromagnetic fields. It begins by discussing electrostatics and defining electric fields as having their sources in electric charges. It then covers Coulomb's law, which describes the electric force between two charges, and Gauss's law, which relates the electric flux through a closed surface to the electric charge enclosed. The document explains electric field lines and flux, superposition of electric fields, and uses Gauss's law to analyze properties of conductors. Finally, it mentions that the next section will cover electric potential. The key information is that the document serves as an introduction to electromagnetic fields, covering fundamental concepts like Coulomb's and Gauss's laws.
current ,current density , Equation of continuityMuhammad Salman
1. Electric current in metallic conductors is carried by valence electrons, or free electrons, that move under the influence of an electric field. The velocity of these electrons is called the drift velocity.
2. Drift velocity is directly proportional to the electric field intensity and mobility of the electrons in the material. Higher conductivity materials like silver, copper and aluminum have higher electron mobilities.
3. The relationship between current density J and electric field E in a metallic conductor is defined by its conductivity σ, where J = σE. Conductivity depends on the charge density and mobility of electrons in the material.
This document discusses transmission lines and waveguides. It begins by defining key concepts like electrons, energy transfer through current and waves, and how the system used for energy transfer depends on frequency. It then covers topics like transmission lines, coaxial lines, parallel plate waveguides, various waveguide modes, and how circuit theory breaks down at high frequencies due to effects like skin effect. Filters and network analysis are also summarized. The document aims to provide an overview of guided communication systems ranging from circuits to optical fibers.
The document describes an electric field detector that uses ferrite material to detect electric fields over a volume, rather than just a surface area. It discusses how ferrite allows electric fields to penetrate its internal volume. The detector utilizes the microstructure and effects integration of an electric field over the volume of ferrite core. It provides advantages over previous detectors by reducing the effects of stray capacitance coupling and increasing sensitivity. Applications include detecting weak, medium, and strong electric fields from power lines and other energized conductors.
Experiment #{Experiment Title}Date Performed .docxrhetttrevannion
Experiment #
{Experiment Title}
Date Performed:
Date Report Submitted:
Report Author:
Lab Partner[s]:
Instructor’s Name:
Section Number:
I. Introduction
Three sentences are fine for the introduction. State what you measured, what you calculated, and what you are comparing your results to. Avoid using first person in the report. This section is 5 points. Refer to Appendix B and your Lab 1 Report for full instructions.
II. Data
This section is worth 20 points.
All measurements must be included and have proper unites and significant figures.
Data needs to be neat and understandable with explanations or equations.
Put in-lab data sheets signed behind this page when submitting the paper copy of your report.
The “data” heading can stay on the same page as the introduction or be hand written on top of the data sheet.
Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
III. Data Analysis
This section is worth 30 points. It contains the calculations, graphs, and sample calculations if one was performed repeatedly. Always calculate a percent difference between experimental and theoretical vales. There are directions on how to set up graphs in Appendix B.
You can use Word to type equations by clicking “Equation” on the “Insert” Tab or by clicking Alt and = simultaneously. Word lets you use Latex or Unicode to type equations. It also has buttons to press to insert symbols under the new “Design” tab if you do not know Latex or Unicode. If you hover over button, it will tell you how to type it using Latex or Unicode (whatever is selected)
The hypotenuse length can be found using the side lengths:
Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
IV. Discussion
This section will contain a table of summary results and paragraphs discussing the accuracy of results, the sources of errors, and the physics or answers to questions. Below is a sample summary table. Please be sure to update it or replace it with a table for the correct information.
Table 1 : Summary of Results
Measured Diameter [m]
Error in Measured
Theoretical Diameter [m]
%Difference
It is important to discuss types of error and largest error in your experiment. Refer to Section D of Appendix B and the Discussion from Lab 1 for more information.
V. Conclusion
You only need two sentences minimum and this section is worth 5 points. Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
2
Experiment 2
Electric Potential and Field Mapping
Introduction
In this experiment, you use a voltage probe and a computer data acquisition system to
measure the electric potential between two metal electrodes. The electrodes are placed in a tray,
which contains a shallow layer of water. The electrodes are connected to a D.C. power supply,
which maintains a constant potential difference. The water allows an electric current to flow
fr.
Experiment #{Experiment Title}Date Performed .docxnealwaters20034
Experiment #
{Experiment Title}
Date Performed:
Date Report Submitted:
Report Author:
Lab Partner[s]:
Instructor’s Name:
Section Number:
I. Introduction
Three sentences are fine for the introduction. State what you measured, what you calculated, and what you are comparing your results to. Avoid using first person in the report. This section is 5 points. Refer to Appendix B and your Lab 1 Report for full instructions.
II. Data
This section is worth 20 points.
All measurements must be included and have proper unites and significant figures.
Data needs to be neat and understandable with explanations or equations.
Put in-lab data sheets signed behind this page when submitting the paper copy of your report.
The “data” heading can stay on the same page as the introduction or be hand written on top of the data sheet.
Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
III. Data Analysis
This section is worth 30 points. It contains the calculations, graphs, and sample calculations if one was performed repeatedly. Always calculate a percent difference between experimental and theoretical vales. There are directions on how to set up graphs in Appendix B.
You can use Word to type equations by clicking “Equation” on the “Insert” Tab or by clicking Alt and = simultaneously. Word lets you use Latex or Unicode to type equations. It also has buttons to press to insert symbols under the new “Design” tab if you do not know Latex or Unicode. If you hover over button, it will tell you how to type it using Latex or Unicode (whatever is selected)
The hypotenuse length can be found using the side lengths:
Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
IV. Discussion
This section will contain a table of summary results and paragraphs discussing the accuracy of results, the sources of errors, and the physics or answers to questions. Below is a sample summary table. Please be sure to update it or replace it with a table for the correct information.
Table 1 : Summary of Results
Measured Diameter [m]
Error in Measured
Theoretical Diameter [m]
%Difference
It is important to discuss types of error and largest error in your experiment. Refer to Section D of Appendix B and the Discussion from Lab 1 for more information.
V. Conclusion
You only need two sentences minimum and this section is worth 5 points. Refer to Appendix B and your Lab 1 Report for full instructions and how to achieve full points.
2
Experiment 2
Electric Potential and Field Mapping
Introduction
In this experiment, you use a voltage probe and a computer data acquisition system to
measure the electric potential between two metal electrodes. The electrodes are placed in a tray,
which contains a shallow layer of water. The electrodes are connected to a D.C. power supply,
which maintains a constant potential difference. The water allows an electric current to flow
fr.
1) An inductor opposes changes in current and stores energy in a magnetic field. A capacitor consists of conductors separated by an insulator and stores energy in an electric field. Inductors and capacitors are passive elements that can store but not generate energy.
2) The voltage across an inductor is proportional to the rate of change of current through it. The current through a capacitor is proportional to the rate of change of voltage across it.
3) Inductors and capacitors can be combined in series or parallel configurations, with equivalent inductance/capacitance values that are the sum/reciprocal sum of the individual components respectively.
This document provides an overview of transmission line modeling and analysis. It begins with assigning homework problems and then reviews electric field concepts such as Gauss's law and voltage difference calculations. Models for transmission line capacitance and inductance are developed considering both single and multi-conductor cases. Examples are provided to demonstrate how to calculate per phase capacitance, resistance, and inductance values for different conductor types using data from standard tables. Additional transmission line topics like multi-circuit lines, underground cables, and corona discharge are also briefly discussed.
This document provides a summary of key concepts in radio frequency (RF) acceleration for particle accelerators. It discusses early electrostatic accelerators like the Van de Graaff and their limitations. It then introduces the concept of RF acceleration using oscillating electric fields to continuously accelerate particles. Key RF acceleration techniques are summarized, including drift tube linear accelerators, cavity linacs, and the resonant TM010 mode used in most RF cavities. Important cavity concepts like the quality factor, resonant frequencies, and accelerating voltage are defined. Peak surface fields, power dissipation, and the equivalent circuit model of cavities including their shunt impedance are also covered at a high level.
The document discusses various mechanisms of charge carrier transport in semiconductors including drift and diffusion. It defines carrier drift as the movement of electrons and holes under the influence of an applied electric field. Carrier mobility is introduced as a material property that determines how fast carriers drift in response to an electric field. Diffusion is defined as the movement of carriers from areas of high concentration to low concentration due to random thermal motion. The Einstein relation links diffusion and mobility through the carrier temperature. Total current in a semiconductor is the sum of drift and diffusion currents.
This document provides an overview of electrostatics. It defines key concepts like electric field, electric flux density, Gauss's law, capacitance, and more. Applications of electrostatics include electric power transmission, X-ray machines, solid-state electronics, medical devices, industrial processes, and agriculture. Coulomb's law describes the electric force between point charges. Gauss's law relates the electric flux through a closed surface to the enclosed charge. Capacitance is the ratio of stored charge on conductors to the potential difference between them.
- Electrochemical impedance spectroscopy (EIS) measures the impedance of electrical circuits and chemical systems as a function of frequency. It provides more detailed information than DC techniques alone.
- Impedance replaces resistance as a more general parameter that accounts for frequency-dependent behavior of circuit elements like capacitors and inductors. It is defined as the ratio of voltage to current.
- EIS experiments involve applying a small AC potential over a range of frequencies and measuring the current response. The impedance is calculated from these measurements and plotted on Nyquist and Bode plots for analysis.
- Equivalent circuit models consisting of electrical components like resistors and capacitors are used to model electrochemical systems and interpret EIS data
The document summarizes an experiment on analyzing series and parallel RLC circuits. It describes:
1) Calculating the theoretical resonance frequency of a series RLC circuit as 18.8 kHz, but measuring it experimentally as 16.73 kHz, a difference of 11.1%.
2) Plotting the output voltage versus frequency, which reaches a minimum at the theoretical resonance point.
3) Analyzing the phase relationship and impedance characteristics at resonance, finding the voltage and current are in phase.
Hall generators and low resistance shunts are used to measure high direct currents. Hall generators use the Hall effect - when a current-carrying conductor is placed in a magnetic field, a voltage is produced perpendicular to the current and field. This voltage is proportional to the current. Low resistance shunts measure the small voltage drop across the shunt, which is proportional to the current.
Current transformers are used to measure high power alternating currents, as they provide electrical isolation. Electro-optical techniques transmit the voltage signal through an optical fiber to improve accuracy at high voltages.
Resistive shunts, magnetic probes, and Hall/Faraday effect devices are used for high frequency and impulse currents. Res
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2. Unit-1b: Smart Sensor
Sensor Characteristics:
There are various conversion steps which are performed before an electrical
signal is generated in a sensor from a given stimulus.
Take for example a pressure detection with optical fiber.
1. Pressure produce a strain in the fiber
2. That changes the refractive index of the fiber material
3. That changes the optical transmission and modulation of the photon
density
4. Then the modulated photon density is detected and converted into an
electrical signal using photoresistive phenomenon etc.
If there are lots of conversions, then we must have some way to
estimate the output at every conversion.
3. Sensor Characterization continued
)
(s
f
S
This function can be a linear or exponential or some other complex
function. But in many cases it’s a linear function of the type
bs
a
S
Here a is the intercept and b is the
slope or it is also called sensitivity.
s
S
Input
Output
1. Transfer function.
There is an ideal or a theoretical relationship between the stimulus and output it
generate. This ideal function could a table of values or a graph or a mathematical
equation. This ideal output-stimulus relationship is called a transfer function. This
relationship describes the dependence of the a stimulus s on the electrical signal S.
5. 2. Span (Input full scale)
The dynamic range of stimuli which may be converted by a sensor is called a
span or an input full scale (FS). It represents the highest possible input value
which can be applied to a sensor.
This dynamic range is often expressed in decibels which is a logarithmic
measure of ratios of either power or voltage.
3. Full Scale Output (FSO)
The algebraic difference between the end points of
the outputs for maximum input and lowest input
stimulus. The upper limit of a sensor output over
the measured range is called the full scale.
1
2
log
10
1
P
P
dB
Sensor Characterization continued
s
S
Input
Output
FSO
6. 3. Accuracy
Accuracy of a sensor really means inaccuracy, that is
the highest deviation of a value from its ideal value.
4. Calibration Error
Calibration Error is inaccuracy
permitted by a manufacturer when a is
calibrated in the factory. This is a
systematic error which is added to all
possible real transfer function.
5. Hysteresis
The maximum difference in output, at
any measured value, within the
measured range when the value is
approached first with increasing and
decreasing measurand. It is expressed in
% of FSO during one calibration cycle.
Sensor Characterization continued
Hysteresis
7. Sensor Characterization continued
Nonlinearity error is
specified for sensors
whose transfer function
may be approximated
by a straight line. So it
measures a maximum
deviation (L) of a real
transfer function from
the approximate straight
line
The value of measurand over which the sensor is intended to measure
specified by upper and lower limits.
7. Measurand Range
6. Nonlinearity
8. 8. Resolution.
The minimum change of the measurand value necessary to produce a
detectable change at the output.
9. Selectivity
The ability of a sensor to measure one measurand ( e,g., one chemical
component ) in the presence of others.
Sensor Characterization continued
10. Sensitivity.
The ratio of the change in sensor output to the change in the
input of a measurand. It is the slope of the transfer curve.
o
s
s
ds
s
dS
b
)
(
11. Ambient Conditions Allowed
Ambient conditions can strongly influence the operation of a sensor.
These conditions include temperature, moisture, ambient pressure,
vibrations, shock, acceleration and EM field.
9. Electrical and other fundamentals:
Electric charges, field and potentials:
We consider interaction between charges mainly in the following
mediums :
• Conductors,
• Semiconductors
• Insulators
• Fluids
These materials are characterized by their electric properties, like
dielectric constant, resistivity etc.
10. Electric Charges, Fields, and Potentials
• Positive test charge in
vicinity of a charged object
• (a) and electric field of a
spherical object (b)
• If a small positive electric
test charge q0 is positioned
in the vicinity of a charged
object, it will be subjected
to a repelling electric force
11. Gauss’ law
• If we imagine a hypothetical closed surface (Gaussian
surface) S, a connection between the charge
q and flux can be established as
where the integral is equal to
If a surface encloses equal and opposite charges, the net flux is
zero. The charge outside the surface makes no contribution to the
value of q, nor does the exact location of the inside charges affect this
value.
The Coulomb law itself can be derived from the Gauss’ law.
It states that the force acting on a test charge is inversely
proportional to a squared distance from the charge
12. How to calculate an electric field at a given point in a medium?
The Gauss’ law
Q
dS
E
o
.
=total charge enclosed within that surface)
Q
E
dS
E=electric field
dS is the surface element
Examples: How to calculate the electric field of the following
charge distributions?
• Spherical symmetric charge distribution
Q
dS
E
o
.
Q
r
E
o
2
4
Total surface
area of a
sphere = 2
4 r
+Q
2
4
1
r
Q
E o
13. +Q r
Inside a uniform sphere of charge Q
R
dS
E
o
.
charge enclosed within the radius
r of the big sphere of radius R
3
3
2
4
R
r
Q
r
E
o
3
4
1
R
Qr
E o
the electric field inside a uniform sphere of charge q is directed
radially and has magnitude
14. Infinite Charged Line
We construct a Gaussian surface, which is
a ring of radius r around the wire.
is the charge per unit length of the wire.wire
Note that the electric field varies as
r
1
If the electric charge is distributed along an
infinite (or, for the practical purposes, long)
line, the electric field is directed
perpendicularly to the line and has the
magnitude
where r is the distance from the line and l is the linear charge
density (charge per unit length).
15. Electric field near an infinite sheet
The electric field due to an infinite
sheet of charge is perpendicular to
the plane of the sheet and has
magnitude
16. Electric filed between the two charged sheets or
between parallel plate condensers
++
+
+
+
+
+
-
-
-
-
-
-
-
Electric field E is directed from one sheet
to another
o
o
o
E
E
E
2
2
17. Electric dipole (a); an electric dipole in an electric
field is subjected to a rotating force (b)
An electric dipole is a combination
of two opposite charges which are
placed at a distance 2a apart.
Each charge will act on a test
charge with force which defines
electric fields E1 and E2 produced
by individual charges.
A combined electric field of a
dipole, E, is a vector sum of two
fields. The magnitude of the field is
where r is the distance from the center of the
dipole
Where dipole moment p =2qa
18. Electric potential:
It is the amount of work done per unit charge against the external electric field to
bring a charge to a particular point r in a medium. That defines the electric
potential associated with that point.
A
Charge Q
B
Electric field E
B
A V
V
-work done =-F.dr =- E.dr
B
A
o
B
A
o
r
r
Q
r
Q
dr
V
1
1
4
4
1
2
Potential at a distance r from the charge +Q is
r
Q
V o
4
1
One can obtain this if we take the
point B to infinity and assume rA = r
Units of the potential are
Volt = Joule/Coulomb dr
E
V .
Since E
dr
dV
Gradient of potential
gives the electric field
19. Capacitance
V
Q
C
Capacitance
is defined as
On what factors the value of C
depends?
Medium between the plates,
shape of the plates,
distance between the plates
Fluctuating
current
C
j
i
V
1
Electric field E
A= area
of the
plate
+
+
+
+
+
+
-
-
-
-
-
-
+Q -Q
Voltage applied =V
+ -
d
The phenomenon of a
capacitance is used in many
sensors.
20. Capacitance continued
Capacitance between the two parallel plates can also be defined as
d
A
C 0
It is the capacitance dependence of the
above factors which is exploited in most of
the sensors design.
For a cylindrical capacitor
a
b
L
C
ln
2
0
L
+Q
-Q
a
b
21. Dielectric Constant
The presence of a medium between the plates of a capacitor
modifies the electric field between the plates.
So the effective dielectric
constant becomes
d
A
C
V
Q
C
0
0
One can think of making a
sensor where k is changes by
a stimulus.
Think also of series and
parallel capacitors
24. Another Example of Capacitor
• Another example of a capacitive
sensor is a humidity sensor.
• In such a sensor, a dielectric
between the capacitor plates is
fabricated of a material that is
hygroscopic, that is, it can
absorb water molecules.
• Material dielectric constant
varies with the amount of
absorbed moisture, this changes
the capacitance that can be
measured and converted to a
value of relative humidity
The dependence is not perfectly linear but
this usually can be taken care of during the
signal processing
26. Resistance
Resistance of a material is
defined as
i
V
R
a = area of cross-section of
the material
Temperature dependence of resistivity
)
(
1 o
o T
T
•Resistivity of a material can be
expressed through
•mean time between collisions, τ,
•the electronic charge, e,
•the mass of electron, m, and
•a number of conduction electrons
per unit volume, n
28. Moisture Sensitivity
• By selecting material for a resistor, one
can control its specific resistivity and
susceptibility of such to the
environmental factors.
• One of the factors that may greatly
affect r is the amount of moisture that
can be absorbed by the resistor.
• A moisture-dependent resistor can be
fabricated of a hygroscopic material
whose specific resistivity is strongly
influenced by concentration of the
absorbed water molecules.
• This is the basis for the resistive
humidity sensors, which are called
hygristors.
A typical hygristor is comprised of a ceramic
substrate that has two silk-screen printed
conductive inter-digitized 7 electrodes
29. Piezoelectric effect
It is generation of electric charge by a crystalline material when
subjected to an external stress.
Example of materials: Quartz ( chemical formula SiO2, , man made
ceramics and some polymers, such as PVDF
How the charges are created?
To pick up the electric field, conductive electrodes must be applied
to the opposite side of the crystal cut. As a result a piezoelectric
material becomes a capacitor with voltage V across the capacitor.
30. The word piezo comes
from the Greek meaning “to press.”
• The Curie brothers discovered the piezoelectric effect in
quartz in 1880, but very little practical use was made until
1917 when another Frenchman, professor P. Langevin used
x-cut plates of quartz to generate and detect sound waves
in water.
• His work led to the development of sonar.
31. Piezoelectric effect is a
reversible phenomenon.
Which means that the
applied voltage across
the material will
produce a strain.
The polarization vector P is given
by
zz
yy
xx P
P
P
P
Piezoelectric effect
Piezoelectric sensor is formed by applying electrodes
to a poled crystalline material
32. zz
yy
xx
xx d
d
d
P
13
12
11
zz
yy
xx
yy d
d
d
P
23
22
21
zz
yy
xx
zz d
d
d
P
33
32
31
When we apply a stress to the crystal we generate
polarization.
Let dij are the piezoelectric coefficient along the orthogonal
directions. Then
Charge generated by a piezoelectric crystal is proportional to
applied force.
x
x F
d
Q 11
For x-direction
Voltage generated in a Piezoelectric crystal
33. So the voltage developed will be
x
F
C
d
C
Qx
V 11
l
a
C o
Capacitance can be written in terms of the
electrode surface area , a, and thickness l
Then the output voltage
becomes x
o
x F
a
l
d
F
C
d
V
11
11
34. Piezoelectric Sensor is AC or DC Device?
• When stress is applied, or air blows near its surface the balanced
state is degraded and the piezoelectric material develops an
electric charge.
• If the stress is maintained, the charges again will be neutralized
by the internal leakage.
• Thus, a piezoelectric sensor is responsive only to a changing
stress rather than to a steady level of it.
• In other words, a piezoelectric sensor is an AC device, rather
than a DC device.
• The three most popular materials are zinc oxide (ZnO),
aluminum nitride (AlN), and the so-called solid solution system
of lead-zirconite-titanium oxides Pb(Zr,Ti)O3 known as PZT
ceramic
38. Which material preferred?
• Zinc oxide in addition to the piezoelectric properties also is
pyroelectric. It was the first and most popular material for
development of ultrasonic acoustic sensors, surface acoustic
wave (SAW) devices, microbalances, etc. One of its advantages
is the ease of chemical etching. The zinc oxide thin films are
usually deposited on silicon by employing the sputtering
technology.
• Aluminum nitride (AlN) is an excellent piezoelectric material
because of its high acoustic velocity and its endurance in
humidity and high temperature. Its piezoelectric coefficient is
somewhat lower than in ZnO but higher than in other thin-film
piezoelectric materials, excluding ceramics. The high acoustic
velocity makes it an attractive choice in the GHz frequency
range.
39. • Usually, the AlN thin films are fabricated by using the
chemical vapor deposition (CVD) or reactive molecular
beam epitaxy (MBE) technologies. However, the drawback
of using these deposition methods is the need for high
heating temperature (up to 1,300C) of the substrate.
• The PZT thin films possess a larger piezoelectric coefficient
than ZnO or AlN, and also a high pyroelectric coefficient,
which makes it a good candidate for fabrication of the
thermal radiation detectors.
• A great variety of deposition techniques is available for the
PZT, among which are the electron-beam evaporation [11],
RF sputtering [12], ion-beam deposition [13], epitaxial
growth by RF sputtering [14], magnetron sputtering [15],
laser ablation [16], and sol-gel [17]
Which material preferred?
40. Polymer Piezoelectric Films
• In 1969, H. Kawai discovered a strong piezoelectricity in
polyvinylidene fluoride (PVDF) and in 1975 the Japanese
company Pioneer, Ltd. developed the first commercial
product with the PVDF as a piezoelectric loudspeakers and
earphones.
• PVDF is a semicrystalline polymer with an
approximate degree of crystallinity of 50%
41. Some unique properties of the piezoelectric films are
(from Measurement Specialties Inc., www.msiusa.com)
• Wide frequency range - 0.001 Hz to 109 Hz.
• Vast dynamic range (10-8 to 106 psi or micro-torr to Mbar).
• Low acoustic impedance – close match to water, human tissue and adhesive
systems.
• High elastic compliance.
• High voltage output – 10 times higher than piezo ceramics for the same force
input.
• High dielectric strength – withstanding strong fields (75 V/micro-m) where
most piezo ceramics depolarize.
• High mechanical strength and impact resistance (109—1010 Pascal
modulus).
• High stability—resisting moisture (<0.02% moisture absorption), most
chemicals, oxidants, and intense ultraviolet and nuclear radiation.
• Can be fabricated into many shapes.
• Can be glued with commercial adhesives.