AC1 Fundamentals Unit 3 – Inductance
Exercise 1 – Inductors
EXERCISE OBJECTIVE
When you have completed this exercise, you will be able to describe the effect an inductor has
on dc and ac circuits by using measured values. You will verify your results with an oscilloscope
and multimeter.
EXERCISE DISCUSSION
- A dc current passing through an inductor only encounters opposition from the resistance of
the wire; therefore, no counter emf is produced. - An ac current creates a counter emf that is proportional to the signal frequency and the
amount of inductance. - Increased inductance creates increased opposition to current flow and therefore, increased
counter emf. - Increased signal frequency creates increased opposition to current flow and therefore,
increased counter emf. - Inductance causes a 90 degree phase shift between the voltage and the current. The voltage
across the inductor leads the current.