Unit 11

Question 1

Electromagnetic Induction

Answer 1

the process where a changing magnetic field induces an EMF cross a conductor placed in the field.

Question 2

Magnetic Flux

Answer 2

the number of field lines passing through a surface (measured in Webers (Wb)).

Question 3

Magnetic Flux Linkage

Answer 3

the total magnetic flux across a coil.

Question 4

Faraday’s Law

Answer 4

the induced emf in a circuit is equal to the rate of change of magnetic flux linkage through the circuit.

Question 5

Lenz’s Law

Answer 5

the direction of the induced current is such as to oppose the change that produced the current.

Question 6

The rms Value

Answer 6

the dc current or voltage that would produce the same power output as a given AC supply

Question 7

Capacitance

Answer 7

the charge per unit voltage which the capacitor is capable of maintaining

Question 8

Time Constant

Answer 8

τ, is the time it would take for the capacitor to charge/discharge if the capacitor were to keep charging/discharging at its initial rate.
(the time taken for the capacitor to discharge to 0.37 (1/e) of its original charge.)

Question 9

Half-life of a capacitor

Answer 9

The half life of a capacitor, t1/2, is the time taken for the potential difference across the capacitor to halve