This document contains 30 multiple choice questions about wave properties and behaviors. The questions cover a range of topics including:
- Characteristics of progressive and stationary waves
- Interference and superposition of waves
- Speed, frequency, wavelength and amplitude of waves
- Types of electromagnetic waves and their properties
- Reflection, refraction, and polarization of light
- Sound waves and resonance in pipes and tubes
1) O documento é um teste de avaliação de Ciências Naturais para alunos do 7o ano.
2) O teste contém questões sobre o Universo, Sistema Solar, origem da vida e evolução.
3) Os alunos devem escolher opções corretas, ordenar eventos cronologicamente e identificar conceitos.
The document discusses sewing tools, materials, and equipment. It identifies various measuring tools like tape measures and rulers, cutting tools like shears and seam rippers, and marking tools such as tailor's chalk. It also covers sewing accessories, including thimbles and pins, as well as pressing equipment like ironing boards and sleeve boards. Maintaining sewing tools is important as it keeps them in good condition and prevents damage, allowing them to last a long time. Proper care includes keeping tools dry, clean and organized.
Correção do teste de avaliação sociedades recoletoras produtorasPatrícia Morais
O documento resume informações sobre a evolução humana e as primeiras sociedades, incluindo: (1) os primeiros vestígios de antepassados humanos surgiram na África; (2) o Homo Erectus aprendeu a produzir fogo, trazendo vantagens como aquecimento e defesa; (3) no Paleolítico as pessoas praticavam caça, coleta e um estilo de vida nômade.
1) A ficha de avaliação testa o conhecimento dos alunos sobre conceitos básicos de geografia como linhas imaginárias, coordenadas geográficas e localização de continentes e mares.
2) Os alunos devem identificar linhas como o meridiano, o equador e os trópicos, e classificar afirmações sobre esses conceitos como verdadeiras ou falsas.
3) Eles também precisam localizar pontos em um mapa usando suas coordenadas geográficas e responder perguntas sobre os limites naturais e ma
O documento é uma ficha de avaliação de um aluno do 5o ano sobre História e Geografia de Portugal. A ficha indica que o aluno revelou algumas dificuldades em adquirir os conhecimentos, mas que estudando mais pode superá-las. A ficha inclui várias perguntas sobre as primeiras comunidades humanas em Portugal e a influência dos Romanos.
Este documento fornece as coordenadas geográficas de cinco locais (M, N, O, P) e apresenta um teste sobre elementos da superfície terrestre e representações cartográficas, incluindo uma ficha de avaliação.
1) O documento é um teste de avaliação de Ciências Naturais para alunos do 7o ano.
2) O teste contém questões sobre o Universo, Sistema Solar, origem da vida e evolução.
3) Os alunos devem escolher opções corretas, ordenar eventos cronologicamente e identificar conceitos.
The document discusses sewing tools, materials, and equipment. It identifies various measuring tools like tape measures and rulers, cutting tools like shears and seam rippers, and marking tools such as tailor's chalk. It also covers sewing accessories, including thimbles and pins, as well as pressing equipment like ironing boards and sleeve boards. Maintaining sewing tools is important as it keeps them in good condition and prevents damage, allowing them to last a long time. Proper care includes keeping tools dry, clean and organized.
Correção do teste de avaliação sociedades recoletoras produtorasPatrícia Morais
O documento resume informações sobre a evolução humana e as primeiras sociedades, incluindo: (1) os primeiros vestígios de antepassados humanos surgiram na África; (2) o Homo Erectus aprendeu a produzir fogo, trazendo vantagens como aquecimento e defesa; (3) no Paleolítico as pessoas praticavam caça, coleta e um estilo de vida nômade.
1) A ficha de avaliação testa o conhecimento dos alunos sobre conceitos básicos de geografia como linhas imaginárias, coordenadas geográficas e localização de continentes e mares.
2) Os alunos devem identificar linhas como o meridiano, o equador e os trópicos, e classificar afirmações sobre esses conceitos como verdadeiras ou falsas.
3) Eles também precisam localizar pontos em um mapa usando suas coordenadas geográficas e responder perguntas sobre os limites naturais e ma
O documento é uma ficha de avaliação de um aluno do 5o ano sobre História e Geografia de Portugal. A ficha indica que o aluno revelou algumas dificuldades em adquirir os conhecimentos, mas que estudando mais pode superá-las. A ficha inclui várias perguntas sobre as primeiras comunidades humanas em Portugal e a influência dos Romanos.
Este documento fornece as coordenadas geográficas de cinco locais (M, N, O, P) e apresenta um teste sobre elementos da superfície terrestre e representações cartográficas, incluindo uma ficha de avaliação.
1. The document contains questions about wave interference and diffraction concepts.
2. It includes multiple choice questions about wave superposition, diffraction gratings, and interference patterns.
3. Diagrams are provided with some questions to illustrate wave concepts like path differences and interference maxima.
J2 Physics 2008 Lasers & semiconductors prelim questions John Jon
Population inversion refers to a situation where the number of atoms in an excited higher energy state exceeds the number of atoms in a lower energy state. This condition is necessary to achieve laser action through stimulated emission. When population inversion is present, incident photons cause stimulated emission of photons of the same frequency and phase, leading to amplification of the light beam in the laser cavity.
Simulation and Performance of AC Drives Using SVPWM Techniquerahulmonikasharma
Drives are mainly categorized into constant-speed and variable-speed drives. AC machines have been used in constant-speed applications, where as DC machines were preferred for variable speed drives. Due to the advancement in power semiconductor devices and microprocessors, AC machines are widely used in variable speed drives. This paper focuses on the simulation and performance evaluation for an ac drive system with Induction motor and PMSM Motor. The focus was based on the simulation of the power circuits using MATLAB/SIMULINK software. The performance of inverter was studied by SVPWM technique. Space Vector Pulse Width Modulation (SVPWM) is a digital technique, which increases the output voltage capability and increases DC bus utilization voltage. The performance of an ac drive system was simulated and evaluated for variable speed operation from no load to rated speed under constant torque operation. The advantages and disadvantages of Induction motor and PMSM are analyzed and presented in this paper.
J2 Physics 2008 prelim questions (Alternating current) John Jon
1. An AC generator produces a sinusoidal voltage. If the frequency is increased from 20 Hz to 30 Hz and the magnetic flux density is reduced, the peak output voltage will be 1.6 V.
2. If a 2.0 Ω resistor is connected to an AC supply with a peak voltage of 10 V across it, the RMS current flowing through the resistor is 5.0 A.
3. A full-wave rectified waveform would be seen on an oscilloscope connected across a resistor in a circuit with 4 diodes and an AC supply, if one of the diodes is removed.
Periodic material-based vibration isolation for satellitesIJERA Editor
The vibration environment of a satellite is very severe during launch. Isolating the satellitevibrations during
launch will significantly enhance reliability and lifespan, and reduce the weight of satellite structure and
manufacturing cost. Guided by the recent advances in solid-state physics research, a new type of satellite
vibration isolator is proposed by usingperiodic material that is hence called periodic isolator. The periodic
isolator possesses a unique dynamic property, i.e., frequency band gaps. External vibrations with frequencies
falling in the frequency band gaps of the periodic isolator are to be isolated. Using the elastodynamics and the
Bloch-Floquet theorem, the frequency band gaps of periodic isolators are determined. A parametric study is
conducted to provide guidelines for the design of periodic isolators. Based on these analytical results, a finite
element model of a micro-satellite with a set of designed periodic isolators is built to show the feasibility of
vibration isolation. The periodic isolator is found to be a multi-directional isolator that provides vibration
isolation in the three directions.
Periodic material-based vibration isolation for satellitesIJERA Editor
This document presents research on using periodic materials to isolate satellite vibrations during launch. It begins with background on the severe vibrations satellites experience during launch and different vibration isolation methods. It then introduces the concept of using periodic composites, which exhibit frequency band gaps where vibrations are isolated. The document provides theoretical analysis to determine these band gaps based on the material properties and dimensions of the periodic isolator. It also describes preliminary experimental testing that showed a periodic foundation reduced frame vibrations by 60% compared to a non-periodic foundation. Finally, it presents a parametric study exploring how the band gaps are affected by the periodic constant and rubber filling fraction, and describes a finite element model of a satellite with a designed periodic isolator setup
This document provides a sample question paper for Class XII Physics with instructions and questions. It contains 5 sections (A-E) with a total of 26 multiple choice and numerical questions worth 70 marks. Section A has 5 one-mark questions, Section B has 5 two-mark questions, Section C has 12 three-mark questions, Section D has 1 four-mark question and Section E has 3 five-mark questions. The document also provides important physical constants and formulas required to solve the questions.
This document provides a sample question paper for Class XII Physics with instructions and questions. It contains 5 sections (A-E) with a total of 26 questions of varying marks. Section A contains 5 one-mark questions, Section B contains 5 two-mark questions, Section C contains 12 three-mark questions, Section D contains 1 four-mark question and Section E contains 3 five-mark questions. The document also provides physical constants and formulas that may be required to solve the questions.
The document provides an introduction to open channel flow. It defines open channel flow and distinguishes it from pipe flow. Open channels are exposed to atmospheric pressure and have a cross-sectional area that varies depending on flow parameters, while pipe flow is enclosed and has a constant cross-sectional area. The document discusses different types of channel flows including steady/unsteady and uniform/non-uniform flow. It also defines geometric elements of open channel sections such as depth, width, wetted perimeter, and hydraulic radius. Critical depth is introduced as the depth where specific energy is minimum. Specific energy, defined as the total energy per unit weight of flow above the channel bottom, is also summarized.
This document contains an electronics exam with questions about various topics:
1. Cathode ray oscilloscopes (CROs) - including their uses, components, and interpreting traces.
2. Semiconductor diodes - including their structure and use as rectifiers.
3. Transistors - including their structure and use as amplifiers and switches.
4. Logic gates - including their symbols, truth tables, and applications in control systems.
The exam tests understanding of key electronics concepts and ability to analyze circuits using CROs. It contains multiple choice and open response questions requiring explanations and calculations. Correct answers are not provided.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
This document describes how to develop a Microsoft Excel program to aid in sizing and selecting centrifugal pumps for process pumping needs. It outlines the basic model, applicable equations including Bernoulli's equation and Darcy's equation for pressure loss. It also discusses parameters like Reynolds number, friction factor, pipe roughness, and provides the Colebrook equation for calculating friction factor. The document recommends using Excel's Solver tool to iteratively solve the Colebrook equation by setting the friction factor as the target cell and constraints.
This document provides a critical analysis of capacitor-commutated converters (CCC). CCCs are line-commutated three-phase bridge converters that have capacitors in series with the AC phase connections. This reduces reactive power requirements and allows commutation at firing angles normally not possible.
The document presents the operating characteristics of CCCs, including valve voltage stress and attainable control range over different load currents. Mathematical formulations are provided for the DC voltage-current characteristic and commutation angles as a function of current. Equations are derived describing the commutation process and conditions required for commutation to occur.
This document provides an overview of various electronic measurement instruments, with a focus on the cathode-ray oscilloscope (CRO). It discusses the key components of a CRO, including the cathode-ray tube and time-base generator. It also examines other instruments like function generators, sine wave generators, and square wave generators. The objectives are to discuss electronic measurement tools, with emphasis on the versatile CRO. Details are provided on the construction and operation of CROs and how they can be used to make various waveform measurements.
This document discusses the cathode-ray oscilloscope (CRO), which is a versatile instrument used to observe and analyze waveforms by plotting amplitude over time. It describes the key components of a CRO, including the cathode-ray tube, vertical and horizontal amplifiers, time-base generator, and triggering circuit. The document provides details on how these components work together to display input signals on the CRT screen and enable measurements of amplitude, frequency, and phase. It also discusses some applications of CROs and covers topics like time-base generators, oscilloscope amplifiers, and the frequency response of CROs.
This document discusses various methods for measuring blood flow and volume, including the Fick method, dye dilution, thermodilution, electromagnetic flowmeters, Doppler ultrasonography, thermal velocity probes, plethysmography, and photoplethysmography. It provides descriptions and figures to illustrate each method. The figures show diagrams of equipment, waveforms, and principles of operation for different techniques to measure cardiac output, blood velocity, and volume changes related to blood flow.
1. The document discusses electromagnetic concepts such as magnetic flux density, magnetic fields due to different current carrying conductors, and the torque experienced by a coil in a magnetic field.
2. Questions are provided about defining magnetic flux density, sketching magnetic field patterns, calculating torque on a coil, and ensuring the magnetic field is parallel to the coil plane.
3. Key concepts covered include magnetic fields, torque, magnetic flux density, and its SI unit of tesla.
Compilation of questions on electromagnetism (questions only + ans for mcq)John Jon
1. A velocity selector is used to obtain an electron beam with a kinetic energy of 250 eV. Electrons with higher kinetic energies will pass through plate X, while electrons with lower kinetic energies will be deflected by plate Y.
2. When a current passes through a vertical wire PQ, a compass placed next to it may point in any of the four directions shown in the diagrams.
3. A uniform magnetic field applied in the same direction as an electric field maintaining a negatively charged plastic sphere at a constant height will have no effect on the sphere.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document describes problems and solutions from the 16th International Physics Olympiad held in 1985 in Portorož, Slovenia. It discusses both the theoretical and experimental competitions. For the theoretical problems, it provides the problems, data, and outlines solutions for 4 multi-part physics problems related to topics like radio wave interference, the Hall effect, orbital mechanics, and more. For the experimental competition, it describes 2 exercises involving measuring the acceleration of a spinning disk and using magnetic fields to locate hidden magnets.
The document discusses various concepts related to waves including:
1. The amplitude of a wave is inversely proportional to its distance from the source. When amplitude doubles, distance halves.
2. Resonance frequencies of an open organ pipe are calculated based on quarter and three quarter wavelengths.
3. For three different waves, the ratios of their frequencies and wavelengths are given.
4. The detection of waves depends on the number of compressions and rarefactions detected per unit time.
5. Malus' law describes how the intensity of polarized light emerging from polarizers depends on the angle between their polarization axes.
1. When two waves meet at a point in space, their amplitudes add vectorially. Constructive interference occurs when the path difference is an integral multiple of the wavelength, producing loud sounds. Destructive interference occurs when the path difference is an odd multiple of half the wavelength, producing soft sounds.
2. As frequency increases, wavelength decreases. This causes the positions of constructive and destructive interference to shift towards the central axis as the microphone passes through them.
3. Increasing the slit separation in a double-slit experiment doubles the fringe separation in the interference pattern. The slit width does not affect fringe separation but decreases intensity.
1. The document contains questions about wave interference and diffraction concepts.
2. It includes multiple choice questions about wave superposition, diffraction gratings, and interference patterns.
3. Diagrams are provided with some questions to illustrate wave concepts like path differences and interference maxima.
J2 Physics 2008 Lasers & semiconductors prelim questions John Jon
Population inversion refers to a situation where the number of atoms in an excited higher energy state exceeds the number of atoms in a lower energy state. This condition is necessary to achieve laser action through stimulated emission. When population inversion is present, incident photons cause stimulated emission of photons of the same frequency and phase, leading to amplification of the light beam in the laser cavity.
Simulation and Performance of AC Drives Using SVPWM Techniquerahulmonikasharma
Drives are mainly categorized into constant-speed and variable-speed drives. AC machines have been used in constant-speed applications, where as DC machines were preferred for variable speed drives. Due to the advancement in power semiconductor devices and microprocessors, AC machines are widely used in variable speed drives. This paper focuses on the simulation and performance evaluation for an ac drive system with Induction motor and PMSM Motor. The focus was based on the simulation of the power circuits using MATLAB/SIMULINK software. The performance of inverter was studied by SVPWM technique. Space Vector Pulse Width Modulation (SVPWM) is a digital technique, which increases the output voltage capability and increases DC bus utilization voltage. The performance of an ac drive system was simulated and evaluated for variable speed operation from no load to rated speed under constant torque operation. The advantages and disadvantages of Induction motor and PMSM are analyzed and presented in this paper.
J2 Physics 2008 prelim questions (Alternating current) John Jon
1. An AC generator produces a sinusoidal voltage. If the frequency is increased from 20 Hz to 30 Hz and the magnetic flux density is reduced, the peak output voltage will be 1.6 V.
2. If a 2.0 Ω resistor is connected to an AC supply with a peak voltage of 10 V across it, the RMS current flowing through the resistor is 5.0 A.
3. A full-wave rectified waveform would be seen on an oscilloscope connected across a resistor in a circuit with 4 diodes and an AC supply, if one of the diodes is removed.
Periodic material-based vibration isolation for satellitesIJERA Editor
The vibration environment of a satellite is very severe during launch. Isolating the satellitevibrations during
launch will significantly enhance reliability and lifespan, and reduce the weight of satellite structure and
manufacturing cost. Guided by the recent advances in solid-state physics research, a new type of satellite
vibration isolator is proposed by usingperiodic material that is hence called periodic isolator. The periodic
isolator possesses a unique dynamic property, i.e., frequency band gaps. External vibrations with frequencies
falling in the frequency band gaps of the periodic isolator are to be isolated. Using the elastodynamics and the
Bloch-Floquet theorem, the frequency band gaps of periodic isolators are determined. A parametric study is
conducted to provide guidelines for the design of periodic isolators. Based on these analytical results, a finite
element model of a micro-satellite with a set of designed periodic isolators is built to show the feasibility of
vibration isolation. The periodic isolator is found to be a multi-directional isolator that provides vibration
isolation in the three directions.
Periodic material-based vibration isolation for satellitesIJERA Editor
This document presents research on using periodic materials to isolate satellite vibrations during launch. It begins with background on the severe vibrations satellites experience during launch and different vibration isolation methods. It then introduces the concept of using periodic composites, which exhibit frequency band gaps where vibrations are isolated. The document provides theoretical analysis to determine these band gaps based on the material properties and dimensions of the periodic isolator. It also describes preliminary experimental testing that showed a periodic foundation reduced frame vibrations by 60% compared to a non-periodic foundation. Finally, it presents a parametric study exploring how the band gaps are affected by the periodic constant and rubber filling fraction, and describes a finite element model of a satellite with a designed periodic isolator setup
This document provides a sample question paper for Class XII Physics with instructions and questions. It contains 5 sections (A-E) with a total of 26 multiple choice and numerical questions worth 70 marks. Section A has 5 one-mark questions, Section B has 5 two-mark questions, Section C has 12 three-mark questions, Section D has 1 four-mark question and Section E has 3 five-mark questions. The document also provides important physical constants and formulas required to solve the questions.
This document provides a sample question paper for Class XII Physics with instructions and questions. It contains 5 sections (A-E) with a total of 26 questions of varying marks. Section A contains 5 one-mark questions, Section B contains 5 two-mark questions, Section C contains 12 three-mark questions, Section D contains 1 four-mark question and Section E contains 3 five-mark questions. The document also provides physical constants and formulas that may be required to solve the questions.
The document provides an introduction to open channel flow. It defines open channel flow and distinguishes it from pipe flow. Open channels are exposed to atmospheric pressure and have a cross-sectional area that varies depending on flow parameters, while pipe flow is enclosed and has a constant cross-sectional area. The document discusses different types of channel flows including steady/unsteady and uniform/non-uniform flow. It also defines geometric elements of open channel sections such as depth, width, wetted perimeter, and hydraulic radius. Critical depth is introduced as the depth where specific energy is minimum. Specific energy, defined as the total energy per unit weight of flow above the channel bottom, is also summarized.
This document contains an electronics exam with questions about various topics:
1. Cathode ray oscilloscopes (CROs) - including their uses, components, and interpreting traces.
2. Semiconductor diodes - including their structure and use as rectifiers.
3. Transistors - including their structure and use as amplifiers and switches.
4. Logic gates - including their symbols, truth tables, and applications in control systems.
The exam tests understanding of key electronics concepts and ability to analyze circuits using CROs. It contains multiple choice and open response questions requiring explanations and calculations. Correct answers are not provided.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
This document describes how to develop a Microsoft Excel program to aid in sizing and selecting centrifugal pumps for process pumping needs. It outlines the basic model, applicable equations including Bernoulli's equation and Darcy's equation for pressure loss. It also discusses parameters like Reynolds number, friction factor, pipe roughness, and provides the Colebrook equation for calculating friction factor. The document recommends using Excel's Solver tool to iteratively solve the Colebrook equation by setting the friction factor as the target cell and constraints.
This document provides a critical analysis of capacitor-commutated converters (CCC). CCCs are line-commutated three-phase bridge converters that have capacitors in series with the AC phase connections. This reduces reactive power requirements and allows commutation at firing angles normally not possible.
The document presents the operating characteristics of CCCs, including valve voltage stress and attainable control range over different load currents. Mathematical formulations are provided for the DC voltage-current characteristic and commutation angles as a function of current. Equations are derived describing the commutation process and conditions required for commutation to occur.
This document provides an overview of various electronic measurement instruments, with a focus on the cathode-ray oscilloscope (CRO). It discusses the key components of a CRO, including the cathode-ray tube and time-base generator. It also examines other instruments like function generators, sine wave generators, and square wave generators. The objectives are to discuss electronic measurement tools, with emphasis on the versatile CRO. Details are provided on the construction and operation of CROs and how they can be used to make various waveform measurements.
This document discusses the cathode-ray oscilloscope (CRO), which is a versatile instrument used to observe and analyze waveforms by plotting amplitude over time. It describes the key components of a CRO, including the cathode-ray tube, vertical and horizontal amplifiers, time-base generator, and triggering circuit. The document provides details on how these components work together to display input signals on the CRT screen and enable measurements of amplitude, frequency, and phase. It also discusses some applications of CROs and covers topics like time-base generators, oscilloscope amplifiers, and the frequency response of CROs.
This document discusses various methods for measuring blood flow and volume, including the Fick method, dye dilution, thermodilution, electromagnetic flowmeters, Doppler ultrasonography, thermal velocity probes, plethysmography, and photoplethysmography. It provides descriptions and figures to illustrate each method. The figures show diagrams of equipment, waveforms, and principles of operation for different techniques to measure cardiac output, blood velocity, and volume changes related to blood flow.
1. The document discusses electromagnetic concepts such as magnetic flux density, magnetic fields due to different current carrying conductors, and the torque experienced by a coil in a magnetic field.
2. Questions are provided about defining magnetic flux density, sketching magnetic field patterns, calculating torque on a coil, and ensuring the magnetic field is parallel to the coil plane.
3. Key concepts covered include magnetic fields, torque, magnetic flux density, and its SI unit of tesla.
Compilation of questions on electromagnetism (questions only + ans for mcq)John Jon
1. A velocity selector is used to obtain an electron beam with a kinetic energy of 250 eV. Electrons with higher kinetic energies will pass through plate X, while electrons with lower kinetic energies will be deflected by plate Y.
2. When a current passes through a vertical wire PQ, a compass placed next to it may point in any of the four directions shown in the diagrams.
3. A uniform magnetic field applied in the same direction as an electric field maintaining a negatively charged plastic sphere at a constant height will have no effect on the sphere.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document describes problems and solutions from the 16th International Physics Olympiad held in 1985 in Portorož, Slovenia. It discusses both the theoretical and experimental competitions. For the theoretical problems, it provides the problems, data, and outlines solutions for 4 multi-part physics problems related to topics like radio wave interference, the Hall effect, orbital mechanics, and more. For the experimental competition, it describes 2 exercises involving measuring the acceleration of a spinning disk and using magnetic fields to locate hidden magnets.
The document discusses various concepts related to waves including:
1. The amplitude of a wave is inversely proportional to its distance from the source. When amplitude doubles, distance halves.
2. Resonance frequencies of an open organ pipe are calculated based on quarter and three quarter wavelengths.
3. For three different waves, the ratios of their frequencies and wavelengths are given.
4. The detection of waves depends on the number of compressions and rarefactions detected per unit time.
5. Malus' law describes how the intensity of polarized light emerging from polarizers depends on the angle between their polarization axes.
1. When two waves meet at a point in space, their amplitudes add vectorially. Constructive interference occurs when the path difference is an integral multiple of the wavelength, producing loud sounds. Destructive interference occurs when the path difference is an odd multiple of half the wavelength, producing soft sounds.
2. As frequency increases, wavelength decreases. This causes the positions of constructive and destructive interference to shift towards the central axis as the microphone passes through them.
3. Increasing the slit separation in a double-slit experiment doubles the fringe separation in the interference pattern. The slit width does not affect fringe separation but decreases intensity.
The document contains 26 multiple choice questions about electromagnetic induction. The questions cover topics such as induced emf in coils, Lenz's law, and how changing magnetic flux induces currents. They provide examples of coils and conductors moving through magnetic fields to illustrate how induced currents are generated through electromagnetic induction.
1. The document provides solutions to oscillation problems involving simple harmonic motion (SHM).
2. It examines the oscillations of objects submerged in liquids and determines forces, pressure, and displacement using concepts of SHM.
3. Damped oscillations and forced oscillations driven by external periodic forces like water waves are also analyzed in the solutions.
The document contains 23 multiple choice questions related to oscillations and simple harmonic motion. The questions cover various topics including:
1) Calculating maximum velocity, period, frequency, and amplitude for objects undergoing SHM.
2) Distinguishing between damped and forced oscillations.
3) Relating kinetic energy, potential energy, restoring force, and displacement for oscillating systems.
4) Applying concepts of SHM to real world examples like floating blocks, swinging pendulums, and vibrating plates.
Lasers & semiconductors 2008 prelim solutionsJohn Jon
Electrons and holes are urged towards the junction region when the diode is in forward bias. This results in the reduction of the depletion region, thus allowing a current to flow. When a p-d is applied across a p-n junction diode in the forward bias mode, the width of the depletion layer decreases, allowing charge carriers to flow more easily across the junction. In reverse bias mode, the depletion layer width increases, preventing charge flow and making the diode act as an open switch.
J2 Physics 2008 prelim electromagnetic induction (questions + ans for mcq)John Jon
The document contains 26 multiple choice questions about electromagnetic induction. The questions cover topics such as induced emf in coils, Lenz's law, and factors that affect induced current. They provide examples of coils and circuits experiencing changing magnetic fields from magnets and electric currents. The document tests understanding of fundamental concepts in electromagnetic induction.
J2 Physics 2008 prelim solutions Alternating current John Jon
The document lists a series of letters and numbers. It then provides 3 short paragraphs about: 1) How alternating voltage can be stepped up or down with little power loss using transformers compared to direct voltage; 2) A calculation showing a step-up transformer with a turn ratio of 2 taking an input of 120V at 8.33A RMS to an output of 1000V; 3) Mentions overhead power lines are cheaper to install and maintain than underground lines but can be blown against buildings in windy conditions.
JC H2 Physics Formula List/Summary (all topics)John Jon
Some of the concepts might be out of syllabus but I believe most of it is still relevant. It is a very concise summary containing mostly formulas and the Laws that govern Physics. This was done by a Raffles Institution student. I hope you will find this beneficial!
H1 Econs Macroeconomic problems and management Essay QuestionJohn Jon
This is an A level H1 econs essay question(economic growth and unemployment) taken from a good junior college's tutorial. The solution was compiled by me. Enjoy!
- A parachutist falling at constant velocity has a drag force equal to their weight due to the net force being zero.
- Newton's second law and free body diagrams are used to analyze forces on objects like cars and boxes on slopes.
- Impulse is used to relate average force and change in momentum to analyze collisions over short periods of time.
Chapter 2 Governance In Singapore Social Studies NotesJohn Jon
This is my self compiled notes of Chapter 2 : Governance in Singapore of the Upper Secondary Social Studies Textbook. I hope my notes will benefit you.
Communications Mining Series - Zero to Hero - Session 1DianaGray10
This session provides introduction to UiPath Communication Mining, importance and platform overview. You will acquire a good understand of the phases in Communication Mining as we go over the platform with you. Topics covered:
• Communication Mining Overview
• Why is it important?
• How can it help today’s business and the benefits
• Phases in Communication Mining
• Demo on Platform overview
• Q/A
“An Outlook of the Ongoing and Future Relationship between Blockchain Technologies and Process-aware Information Systems.” Invited talk at the joint workshop on Blockchain for Information Systems (BC4IS) and Blockchain for Trusted Data Sharing (B4TDS), co-located with with the 36th International Conference on Advanced Information Systems Engineering (CAiSE), 3 June 2024, Limassol, Cyprus.
In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
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1. 1 Which one of the following is a correct statement with regard to wave motion?
A Two waves are said to be coherent if they vibrate with the same frequency.
B For interference to occur between two sound waves, it is only necessary for them to be at the same place and
time.
C A wave traveling in a straight line will have a wave velocity that changes its magnitude sinusoidally in one period.
D The energy of a progressive longitudinal wave does not propagate along the wave but is trapped within the
oscillation of the particles of the wave.
ACJC 08P1Q20
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2. Fig. 21 is a graphical representation of a longitudinal wave where the vertical axis (Y−axis) denotes the displacement of
particle/s of the progressive wave from equilibrium position where positive and negatives represents displacement
respectively to the right or left of equilibrium position. The horizontal axis (positive X−axis) is distance travelled by the
wave in the direction of propagation of the wave.
Which one of the following set of statements is the most appropriate description of the wave in Fig. 21?
A Location P of the longitudinal wave at this instant is at high pressure.
B Location Q at this instant is at the longitudinal wave's antinode.
C Locations P and R of the longitudinal wave are the nodes of the wave.
D Location R of the longitudinal wave at this instant is at high pressure.
ACJC 08P1Q21
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3. A sound source, a plane reflecting surface and a microphone which is connected to a cathode ray oscilloscope (CRO) are
placed in a large chamber containing a gas as shown in Fig. 22.
When the microphone is moved from position P to Q (a distance of 2.00 m) as shown in Fig. 22, the microphone has
moved from an antinode through 5 nodes to another antinode. The CRO is set at a time-base of 1 ms per cm on its display
screen and the distance between 5 adjacent maximum peaks on the screen is 8.4 cm.
Which one of the following gives the most accurate set of values of the wavelength, frequency and the speed of sound in
the chamber?
Speed / m s
-1
Wavelength / m Frequency / Hz
A 476 0.80 595
B 381 0.80 476
C 238 0.40 595
D 191 0.40 476
ACJC 08P1Q22
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4. A warning siren on top of a tall pole is taken to be a point source and radiates sound waves uniformly in all directions. At a
distance 4d, the amplitude of the wave is A. What is the distance from the siren at the point where the amplitude of the
wave is 2A?
A 8d B 4d C 2d D d
AJC 08P1Q20
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2. 5. A tall vertical cylinder is filled with water and a tuning fork vibrating at 400 Hz is held over its open top. The water is slowly
run out and the first resonance of the air column is heard when the water level is 0.21 m below the top of the cylinder.
Neglecting end corrections, how far from the top will the water level be when the next resonance is heard?
A 0.32 m B 0.42 m C 0.63 m D 0.84 m
AJC 08P1Q22
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6. Air filled pipes of equal length are represented in figure below
fa , fb and fc are the frequencies of the fundamental vibrations of the pipes. What is the ratio fa : fb : fc.
. A 1 : 2 : 1 B 1 : 2 : 3 C 2 : 1 : 2 D 3 : 2 : 1
CJC 08P1Q22
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7. Sound travels by means of longitudinal waves in air and solids. A progressive sound wave of wavelength λ and frequency
f passes through a solid from left right. In figure 3.1, the dots on line X represents the equilibrium positions of the atoms in
the solid and dots on line Y represents the positions of the same atoms at a time t = to.
3. (a) Explain why longitudinal waves cannot be polarized. [1]
(b) What does distance D in figure 3.1 represent. [1]
(c) Taking displacement to the right of equilibrium position as positive, sketch on Fig 3.2, a graph of displacement
against distance at time to for Line Y. Label it Y. [2]
(d) Sketch on the same axis given on Fig. 3.2, a graph of displacement against position of the atoms at time = to +
T/4, where T is the period of the wave. Label it Z. [2]
(e) Hence show on Fig. 3.1 on the line Z, the actual position of the particles at time = to + T/4. [2]
(f) Excess pressure is the difference between the pressure at a point above the atmospheric pressure. On figure 3.3,
sketch the graph of excess pressure against distance at different positions at time to. [1]
(g) A person standing on the right side of line Y hears the sound at a frequency of f. Suppose he is moving to the left
along the line Y at a constant speed, he will detect a frequency higher than f. Explain. [1]
CJC 08P3Q3
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8. The table below shows four pairs W, X, Y and Z of polarising sheets cut into uniform circles. Each pair is mounted on the
path of initially unpolarised light. The polarising direction of each sheet is indicated by the dashed line.
Which of the following row gives the correct order for the intensity of the emergent light in decreasing order?
A XYZW
B YWZX
C XZWY
D YXWZ
IJC 08P1Q20
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9. A stationary sound wave was set up in a closed pipe. Which of the following row correctly describes the physical changes
for the displacements of the air particles and the air pressure at the open and closed end of the pipe?
IJC 08P1Q21
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10. Which of the following gives three regions of the electromagnetic spectrum in order of decreasing wavelength?
A microwaves, ultraviolet radiation, infra-red radiation
4. B radio waves, ultraviolet radiation, X-rays
C gamma rays, ultraviolet radiation, microwaves
D visible light, gamma rays, radio waves
JJC 08P1Q23
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11. A wave pulse is traveling to the left as shown in the Fig. 24.1 below. Fig. 24.2 shows the variation with time of the
displacement of a particle P as the pulse passes it.
Which one of the following graphs represents the variation of the displacement with positions of the particles along the
path of the wave pulse at a certain instant?
JJC 08P1Q24
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12. The arrows on the diagrams represent the movement of the air molecules in a pipe in which a stationary longitudinal wave
has been set up. The length of each arrow represents the amplitude of the motion, and the arrow head shows the direction
of motion at a particular instant.
Which of the following diagrams shows a possible stationary wave that could be set up in the pipe?
5. A II only B III only C II and IV D I, II and IV
JJC 08P1Q25
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13. The intensity of a progressive wave is proportional to the square of the amplitude of the wave. It is also proportional to the
square of the frequency.
The variation with time t of displacement x of particles in a medium, when two progressive waves P and Q pass separately
through the medium, are shown on the graphs.
The intensity of wave P is I0.
What is the intensity of wave Q?
A ½ I0 B I0 C 8 I0 D 16 I0
MI 08P1Q21
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14. The figure below shows the relationship between the energy of a photon of electromagnetic radiation E and its wavelength
λ. Points P and Q marked on the graph represent two types of electromagnetic radiation.
Which of the following pairs of electromagnetic radiation correctly identifies P and Q?
P Q
A infra-red X-ray
B microwave gamma ray
C ultraviolet radiowave
D microwave ultraviolet
MJ 08P1Q17
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15. At a particular instant the profile of a surface wave on water is as indicated below.
Which of the graphs below best represents the vertical velocity of the water molecules at this instant, taking upward
velocity as positive?
6. MJ 08P1Q18
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16. Consider a tube of length 32.8 cm which is open at both ends. When a vibrating tuning fork is held close to one end of the
tube, a loud sound is detected. If the velocity of sound in air is 345 ms-1, what is the frequency of vibration of the fork?
A 789 Hz B 526 Hz C 263 Hz D 175 Hz
NJ 08P1Q21
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17. Chi Ching draws a diagram to show different regions of air molecules for a progressive sound wave moving to the right at
a certain instant. P, Q, R, S and T are particles at the centres of these regions.
Which of the following statement is true?
A R is moving towards the right at that instant.
B Distance between P and T is one wavelength.
C After a period of time, Q moves to the position of S.
D The amplitude of R is always zero.
DHS 08P1Q19
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18. A student blows at the end of a drinking straw of length 10.0 cm. What is the lowest frequency of sound produced? [Speed
of sound in air = 320 m s
-1
]
A 800 Hz B 1600 Hz C 3200 Hz D 4800 Hz
NYJ 08P1Q20
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19. Radar systems use waves of λ = 4.0 cm to detect incoming aircraft. The waves are passed along tubes called waveguides.
One part of the system is shown in the figure below where it is rectangular in shape. The length of 1 side (AB & CD) is 18
cm while the length of the other side (BC & AD) is unknown. Assume no energy is lost by the waves in the waveguide and
there is no phase change upon total internal reflection in the waveguide.
7. A wave R arriving at A can divide at A and reach C via the paths ABC and ADC.
(a) What type of electromagnetic wave does the wave corresponding to in the electromagnetic spectrum? [1]
(b) State and explain the amplitude of the resultant wave at C. [3]
(c) A different waveguide, having the dimensions 20 cm by 9 cm, has a wave T of λ = 16 cm travelling from E in the
direction shown below. A detector is placed at C.
By showing and explaining your working clearly, deduce the signal detected at C. [3]
NYJ 08P2Q4
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20. The figure below shows a displacement - distance graph of a progressive transverse wave at a particular time. The arrows
show the directions in which some of the particles on the wave are moving at that instant.
Which of the following statements about the wave is correct?
A The wave has amplitude 8 m and the phase of the particles on the wave is constantly changing.
B Energy is being transferred by the wave from the right to the left.
C The wave is moving to the right and its wavelength is 3 m.
D Particles P and Q have a phase difference of π radians at the instant shown.
PJ 08P1Q18
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21. Water waves travel across a ripple tank. The horizontal distance between a crest and the neighbouring trough is 25 mm
and the vertical distance between a crest and a trough is 5.0 mm. A crest travels 8.0 cm in 0.50 s. Which one of the
following is correct?
Frequency of the water wave / Hz Amplitude of the water wave / mm
A 3.2 2.5
B 3.2 5.0
C 6.4 2.5
D 6.4 5.0
8. RJ 08P1Q19
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22. The figure below shows how the displacements of air molecules, in a longitudinal progressive wave, from their mean
positions vary with the distances of their mean positions from the source O, at a particular instant. The displacement to the
right is taken to be positive. Which of the following statements is correct?
At this instant,
A points marked P, Q, R, S, T, U and V are rarefactions.
B points marked P, Q, R, S, T, U and V are compressions.
C points marked Q and U are rarefactions and the point S is a compression.
D points marked Q and U are compressions and the point S is a rarefaction.
RJ 08P1Q20
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23. Progressive waves of frequency 300 Hz are superimposed to produce a system of stationary waves in which adjacent
nodes are 1.5 m apart.
What is the speed of the progressive waves?
A 200 m s
-1
B 450 m s
-1
C 900 m s
-1
D 1800 m s
-1
SAJ 08P1Q21
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24. A loudspeaker emits a sound wave of amplitude A and intensity I. After some time, the intensity decreased by 6.00 %. The
corresponding change in amplitude is
A 2.96 %
B 3.05 %
C 94.0 %
D 97.0 %
SRJ 08P1Q16
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25. A microwave transmitter of frequency, f, is placed several metres away from a metal plate deflector. A microwave receiver,
connected to a microammeter, is used to detect nodes and antinodes along the normal from the source to the plate. The
microwave receiver is moved from one node through 10 antinodes to another node, a distance of L m. What is the speed
of the microwave?
A 0.16fL
B 0.18fL
C 0.20fL
D 0.25fL
SRJ 08P1Q19
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26. Fig 19.1 below shows a displacement-position graph of a progressive wave at a particular instant of time and Fig 19.2
represents the displacement-time graph of a particle on the wave.
9. The speed of the wave is
A 0.30 m s
-1
B 0.40 m s
-1
C 300 m s
-1
D 400 m s
-1
VJ 08P1Q19
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27. The figure below shows an arrangement to investigate stationary waves on a stretched string. The stationary wave
appears as shown below when the frequency of the oscillator is set at 75 Hz.
At what frequency must the oscillator be set so as to observe only two loops on the string?
A 15 Hz B 30 Hz C 60 Hz D 75 Hz
VJ 08P1Q21
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28. Which one of the following effects provides direct evidence that light is a transverse, rather than a longitudinal wave?
A Light reflected off the front windscreen of a car is cut-off when a driver wears his sunglasses.
B We can hear but not see round corners.
C Lightning is seen before thunder is heard.
D Light can cause emission of electrons from the surface of a metal.
YJ 08P1Q15
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29. Data is transmitted along glass-fibre cables in the form of pulses of monochromatic red light, each of duration 2.5 ns. What
is the best estimate of the number of wavelengths in each pulse?
A 103
B 106
C 109
D 1012
YJ 08P1Q16
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30. An organ pipe of effective length 1.20 m is closed at one end. Given that the speed of sound in air is 300 m s–1, the two
lowest resonant frequencies are
A 62.5, 125 Hz
B 62.5, 188 Hz
C 125, 250 Hz
D 125, 375 Hz
YJ 08P1Q17
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