AQA A Level Physics复习笔记7.7.2 The Time Constant
The Time Constant The time constant of a capacitor discharging through a resistor is a measure of how long it takes for the capacitor to discharge The definition of the time constant is: The...
AQA A Level Physics复习笔记7.7.1 Charge & Discharge Graphs
Capacitor Charge & Discharge Graphs Charging Capacitors are charged by a power supply (eg. a battery) When charging, the electrons are pulled from the plate connected to the positive ter...
AQA A Level Physics复习笔记7.6.3 Energy Stored by a Capacitor
Energy Stored by a Capacitor When charging a capacitor, the power supply pushes electrons from the positive to the negative plate It therefore does work on the electrons and electrical energ...
AQA A Level Physics复习笔记7.6.2 Parallel Plate Capacitor
Relative Permittivity & Dielectric Constant Permittivity is the measure of how easy it is to generate an electric field in a certain material The relativity permittivity εr is sometimes ...
AQA A Level Physics复习笔记7.6.1 Capacitance
Capacitance Capacitors are electrical devices used to store energy in electronic circuits, commonly for a backup release of energy if the power fails They are in the form of two conductive m...
AQA A Level Physics复习笔记7.5.3 Work Done on a Charge
Work Done on a Charge When a mass with charge moves through an electric field, work is done The work done in moving a charge q is given by: ∆W = q∆V Where: ∆W = change in work done (J) q = c...
AQA A Level Physics复习笔记7.5.2 Graphical Representation of Electric Potential
Graphical Representation of Electric Potential Electric field strength, E and the electric potential, V can be graphically represented against the distance from the centre of a charge, r E, ...
AQA A Level Physics复习笔记7.5.1 Electric Potential
Electric Potential In order to move a positive charge closer to another positive charge, work must be done to overcome the force of repulsion between them Similarly, to move a positive charg...
AQA A Level Physics复习笔记7.4.7 Comparing Gravitational & Electrostatic Forces
Electric Potential In order to move a positive charge closer to another positive charge, work must be done to overcome the force of repulsion between them Similarly, to move a positive charg...
