Physics 3.6 Electricity

State Kirchoff’s current law and what it is due to:

The total current entering a junction in a circuit is equal to the total current leaving the junction. This is due to the conservation of charge.

State Kirchoff’s voltage law and what it is due to:

The total voltage around a closed loop in a circuit equals zero. This is due to conservation of energy.

What does EMF stand for and what is it?

EMF is electromotive force and it is the voltage of ideal battery part and the voltage when no current is drawn.

What is terminal voltage and is it more or less than EMF?

Terminal voltage is the voltage of the whole battery. When a current is flowing the terminal voltage is less than the EMF due to a voltage drop across r.

What is the equation for terminal voltage + representing?

Vterminal= EMF - Ir with Ir representing the voltage drop across r

In a graph showing the linear relationship between V and Q what do the gradient and area under the graph represent?

Gradient- capacitance
Area- potential energy stored in capacitor

What are Cd and Ca?

Cd- the capacitance with the dielectric insulating layer
Ca- the capacitance with air or vacuum between the plates

What is capacitance?

Capacitance is a measure of how much charge a capacitor can hold for each 1 volt applied to the capacitor.

What is the time constant of a capacitor?

The time constant of a capacitor is the time taken for the charge (or potential difference) to change by 63.2% of the remaining charge (or potential difference).

What does ε₀ stand for?

Permitivity of free space

How many time constants can a capacitor be said to be fully charge after

5

What type of circuit is this capacitance equation for?

C_T = C₁+C₂+C₃

Parallele

What type of circuit is this capacitance equation for?

1 = 1 + 1 + 1

C_T C₁+ C₂ +C₃

Series