|DCS# 5J10.20||NWU# E-09||Location: Lab Bench|
|title: Energy Stored in an Inductor|
aka: Back EMF
A 1.0 henry inductor (heavy!) is attached to a double throw knife switch so that a current of 3 amperes can be produced in either the inductor or a resistor (adjusted for 3 A).
The current rise time is noted for the reisitor and compared to that of the inductor.
When the current is interupted in the inductor, a large spark appears on the knife switch, but not so with the resistor.
A neon lamp can be attached across the inductor terminals to also flash with the back emf.
Can this spark damage a switch?
Do motors have inductance?