This document discusses several key concepts in electricity including:
1. Electric current is defined as the rate of flow of electric charge through a surface. The SI unit for current is the ampere.
2. Ohm's law states that the current through a conductor is directly proportional to the voltage applied. It is defined by the equation I = V/R where I is current, V is voltage, and R is resistance.
3. Resistance depends on the material properties, length, and cross-sectional area of the conductor. It can also vary with temperature according to its temperature coefficient.
The electric force between two charged particles is:
- Inversely proportional to the square of the distance between them
- Directed along the line joining the particles
- Attractive if charges have opposite signs, repulsive if the same
The electric field E at a point is defined as the electric force on a positive test charge at that point divided by the magnitude of the test charge. Electric field lines are drawn tangent to the field, with a higher density of lines indicating a greater field magnitude.
Georg Simon Ohm was a German physicist born in 1789 who discovered Ohm's Law, which states that the current through a conductor is directly proportional to the voltage applied and inversely proportional to the resistance of the conductor. Ohm spent nine years studying electric circuits experimentally and took great care to ensure accuracy in his experiments. In 1827, he was able to show from his experiments the simple mathematical relationship between resistance, current, and voltage that became known as Ohm's Law. Ohm's Law can be expressed as V=IR, where V is voltage, I is current, and R is resistance.
Coulomb's law describes the electrostatic force between two point charges. The magnitude of the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them. An electric field is a region of space where an electric charge will experience a force, with field lines pointing away from positive charges and toward negative charges. The magnitude of the electric field can be calculated as the force exerted on a test charge divided by the charge, with units of newtons per coulomb.
This document discusses electrostatics and defines key concepts in the field. It begins by defining electrostatics as the branch of physics dealing with charges at rest and their properties. It then provides a brief history, noting that static electricity was first observed by Thales of Miletus in 600 BC and that William Gilbert published the first systematic study of electrostatics in 1600. The document goes on to define concepts like electric charge, fields, dipoles, and flux, and laws such as conservation of charge and Gauss's law.
This document discusses the key parameters - resistance, inductance, and capacitance - of overhead transmission lines.
It first defines each parameter and explains that they are uniformly distributed along the line. Resistance is opposition to current flow, inductance is flux linkages per ampere, and capacitance is charge per voltage.
It then goes on to provide formulas for calculating the resistance, inductance, and capacitance of different types of transmission lines. It also discusses factors like skin effect that impact the resistance and analyses methods for determining flux linkages to calculate inductance.
1) The maximum power transfer theorem states that maximum power is delivered to a load when its resistance equals the internal resistance of the voltage source, as represented by the Thevenin equivalent circuit.
2) When the load resistance is less than the Thevenin resistance, the power delivered to the load decreases rapidly as the load resistance decreases.
3) For maximum power transfer, the load resistance should be set equal to the Thevenin resistance according to the maximum power transfer theorem.
EQUATION OF CONTINUITY AND KIRCHHOFF'S CURRENT LAWGopinathD17
This document discusses the continuity equation in electromagnetics. It states that the rate of decrease of charge within a volume must equal the net outward current flowing out of the surface. This leads to the continuity equation, which for steady currents shows that the total charge leaving a volume equals the total charge entering. When charge is introduced into a material, the volume charge density will decay exponentially over time with a relaxation time constant, which is the time for the charge to drop to 37% of its initial value. Textbooks and references on electromagnetics are also listed.
1. The document describes an experiment to verify Ohm's Law, which states that the current through a conductor is directly proportional to the voltage applied and inversely proportional to the resistance.
2. The experiment involves setting up a circuit with a resistor and voltage source, measuring the current and voltage at different resistances, and showing that a linear relationship exists between current and voltage.
3. The results show that the ratio of voltage to current remains nearly constant at different measurements, and a graph of current versus voltage produces a straight line as expected from Ohm's Law, verifying it experimentally.
Alternating current (AC), is an electric current in which the flow of electric charge periodically reverses direction, whereas in direct current (DC, also dc), the flow of electric charge is only in one direction.
Ohm's law defines the relationship between voltage (V), current (I), and resistance (R) in circuits. V=IR, where V is measured in volts, I in amps, and R in ohms. Resistivity is a measure of how strongly a material opposes the flow of electric current and is represented by the Greek letter rho. It depends on the material's properties but not the size or shape of the object. In series circuits, the current is the same in each component and the total voltage is the sum of the individual voltages. In parallel circuits, the voltage is the same across each branch while the total current is the sum of the branch currents.
This document discusses several key concepts in electricity including:
1. Electric current is defined as the rate of flow of electric charge through a surface. The SI unit for current is the ampere.
2. Ohm's law states that the current through a conductor is directly proportional to the voltage applied. It is defined by the equation I = V/R where I is current, V is voltage, and R is resistance.
3. Resistance depends on the material properties, length, and cross-sectional area of the conductor. It can also vary with temperature according to its temperature coefficient.
The electric force between two charged particles is:
- Inversely proportional to the square of the distance between them
- Directed along the line joining the particles
- Attractive if charges have opposite signs, repulsive if the same
The electric field E at a point is defined as the electric force on a positive test charge at that point divided by the magnitude of the test charge. Electric field lines are drawn tangent to the field, with a higher density of lines indicating a greater field magnitude.
Georg Simon Ohm was a German physicist born in 1789 who discovered Ohm's Law, which states that the current through a conductor is directly proportional to the voltage applied and inversely proportional to the resistance of the conductor. Ohm spent nine years studying electric circuits experimentally and took great care to ensure accuracy in his experiments. In 1827, he was able to show from his experiments the simple mathematical relationship between resistance, current, and voltage that became known as Ohm's Law. Ohm's Law can be expressed as V=IR, where V is voltage, I is current, and R is resistance.
Coulomb's law describes the electrostatic force between two point charges. The magnitude of the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them. An electric field is a region of space where an electric charge will experience a force, with field lines pointing away from positive charges and toward negative charges. The magnitude of the electric field can be calculated as the force exerted on a test charge divided by the charge, with units of newtons per coulomb.
This document discusses electrostatics and defines key concepts in the field. It begins by defining electrostatics as the branch of physics dealing with charges at rest and their properties. It then provides a brief history, noting that static electricity was first observed by Thales of Miletus in 600 BC and that William Gilbert published the first systematic study of electrostatics in 1600. The document goes on to define concepts like electric charge, fields, dipoles, and flux, and laws such as conservation of charge and Gauss's law.
This document discusses the key parameters - resistance, inductance, and capacitance - of overhead transmission lines.
It first defines each parameter and explains that they are uniformly distributed along the line. Resistance is opposition to current flow, inductance is flux linkages per ampere, and capacitance is charge per voltage.
It then goes on to provide formulas for calculating the resistance, inductance, and capacitance of different types of transmission lines. It also discusses factors like skin effect that impact the resistance and analyses methods for determining flux linkages to calculate inductance.
1) The maximum power transfer theorem states that maximum power is delivered to a load when its resistance equals the internal resistance of the voltage source, as represented by the Thevenin equivalent circuit.
2) When the load resistance is less than the Thevenin resistance, the power delivered to the load decreases rapidly as the load resistance decreases.
3) For maximum power transfer, the load resistance should be set equal to the Thevenin resistance according to the maximum power transfer theorem.
EQUATION OF CONTINUITY AND KIRCHHOFF'S CURRENT LAWGopinathD17
This document discusses the continuity equation in electromagnetics. It states that the rate of decrease of charge within a volume must equal the net outward current flowing out of the surface. This leads to the continuity equation, which for steady currents shows that the total charge leaving a volume equals the total charge entering. When charge is introduced into a material, the volume charge density will decay exponentially over time with a relaxation time constant, which is the time for the charge to drop to 37% of its initial value. Textbooks and references on electromagnetics are also listed.
1. The document describes an experiment to verify Ohm's Law, which states that the current through a conductor is directly proportional to the voltage applied and inversely proportional to the resistance.
2. The experiment involves setting up a circuit with a resistor and voltage source, measuring the current and voltage at different resistances, and showing that a linear relationship exists between current and voltage.
3. The results show that the ratio of voltage to current remains nearly constant at different measurements, and a graph of current versus voltage produces a straight line as expected from Ohm's Law, verifying it experimentally.
Alternating current (AC), is an electric current in which the flow of electric charge periodically reverses direction, whereas in direct current (DC, also dc), the flow of electric charge is only in one direction.
Ohm's law defines the relationship between voltage (V), current (I), and resistance (R) in circuits. V=IR, where V is measured in volts, I in amps, and R in ohms. Resistivity is a measure of how strongly a material opposes the flow of electric current and is represented by the Greek letter rho. It depends on the material's properties but not the size or shape of the object. In series circuits, the current is the same in each component and the total voltage is the sum of the individual voltages. In parallel circuits, the voltage is the same across each branch while the total current is the sum of the branch currents.
Deze presentatie gaat over enkele eenvoudige experimenten met elektriciteit bv. een lampje laten branden door een stroomkring te bouwen, een schakelaar bouwen, geleider of isolator, ...
Er wordt ook aandacht gevraagd om zuinig om te springen met energie.
