Datasheet-1

Project 63

FOR ADVANCED USERS - ADULT SUPERVISION RECOMMENDED

High Speed Generator

1mA

Build the circuit and set the meter (M5) to the 1mA scale.

Using the string, make a small loop at one end and put it on a

prong of the motor (M1) top. Wind a few feet of the string

around the motor shaft (wind it so that pulling the string will

spin the motor shaft clockwise).

Pull the string gently but fast, watching the white LED (D6) and

the current produced in the meter. If you wind the string well

and pull it fast, you can briefly light the LED. Get an adult to

help with this if needed.

The LED will light more easily if you remove the meter and

connect the LED where the meter was.

A spare motor top is included with this kit in case you break

any of the prongs on the motor top. Use a screwdriver to pry

off the broken piece, then push the new one on.

This circuit shows how much more current is

produced when you spin the motor shaft faster.

Project 64

Magnetic Energy Released

When you release the switch (turning off power to

the electromagnet), the magnetic field collapses,

releasing energy that lights the white LED. The

magnetic field is stronger when the iron core rod

is in the electromagnet. There is also a small flash

in the LED when the circuit is turned on, setting

up the magnetic field.

Build the circuit, and place the iron core rod into the elec-

tromagnet (M3). Push and release the press switch (S2)

while watching the white LED (D6). Try it with and without

the iron core rod in the electromagnet.

How bright will the white LED flash if you remove the 2-snap

wire from the circuit (to disconnect the electromagnet? (Try it.)

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