Reference: EM55
Category: Electromagnetism
Purpose: Demonstrates back EMF.
Description: A small motor, running off a 2V (or a 3V) battery, is in series with small light bulb. When the motor is running at full speed it draws a very small current and the light only glows dimly. If the motor is slowed down by holding a finger against it lightly, the back EMF drops, and the motor draws more current. The light starts to glow brightly.
