Inductors

Question 1

How can the polarity of induced voltage change?

Answer 1

By reversing the polarity of the magnetic field.

Question 2

Lenz Law

Answer 2

Voltage or current opposes the motion that causes it

Question 3

What happens to the current in an inductive circuit when a resistive load is added to the circuit

Answer 3

Current instantly rises to its maximum. An inductor prevents current from instantly rising.

Question 4

How do you find a time constant?

Answer 4

T=L/R

Time in seconds = Inductance in Henries/Resistance in Ohms

Question 5

Example of an inductor

Answer 5

Motors, transformers, ballasts

Question 6

What is CEMF (counter-electromotive force)

Answer 6

Induced voltage is always opposite in polarity to the applied voltage

Question 7

How are current and voltage related in induced AC currents

Answer 7

Voltage is directly proportional to the rate of current change

Question 8

T or F: an inductor opposes a change of current

Answer 8

True

Question 9

Total inductance (L) in series adds:

Answer 9

Directly

Question 10

Total inductance (L) in parallel adds:

Answer 10

Inversely

Question 11

How do inductors add?

Answer 11

In series = add directly
In parallel = adds inversely