User Guide

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Project #203
OBJECTIVE: To demonstrate how batteries can store electricity.
Build the circuit, then connect points Y & Z (use a 2-snap wire) for a
moment. Nothing appears to happen, but you just filled up the 470μF
capacitor (C5) with electricity. Now disconnect Y & Z and instead touch
a connection between X & Y. The green LED (D2) will be lit and then go
out after a few seconds as the electricity you stored in it is discharged
through the LED and resistor (R2).
Notice that a capacitor is not very efficient at storing electricity -
compare how long the 470μF kept the LED lit for with how your
batteries run all of your projects! That is because a capacitor stores
electrical energy while a battery stores chemical energy.
Make Your Own
Battery
OBJECTIVE: To demonstrate how batteries can store electricity. OBJECTIVE: To demonstrate how batteries can store electricity.
Now replace the 1kΩ resistor (R2) with the 100Ω resistor (R1) and try it.
The LED (D2) gets brighter but goes out faster because less resistance
allows the stored electricity to dissipate faster.
In the preceding circuit, replace the 470μF capacitor (C5) with the
100μF capacitor (C3) and repeat the test. You see that the LED (D2)
goes out faster, because the 100μF capacitor does not store as much
electricity as the 470μF.
Project #204
Make Your Own
Battery (II)
Project #205
Make Your Own
Battery (III)