Capacitors in a Circuit

Exercise Seven: Capacitors and Push Buttons

Background Knowledge:

What you'll need:

1 - 9 Volt Battery

1 - 9 Volt Battery Harness

1 - Breadboard

1 - 1N4007 Rectifier Diode

1 - Momentary PBNO

1 - Momentary PBNC

1 - 470-Ohm 1/4 Watt THR

1 - 2.2 uF 35V Radial Capacitor

1 - 10 uF 35V Radial Capacitor

1 - 100 uF 35V Radial Capacitor

1 - 470 uF 35V Radial Capacitor

1 - 1000 uF 35V Radial Capacitor

1 - Red 5mm LED

Capacitors are electronic components that store electrical energy in an electric field. They consist of two conductive plates separated by an insulating material called a dielectric. The conductive plates can be made of metal, such as aluminum or tantalum, and the dielectric can be made of various materials, such as ceramic, paper, or plastic.

When a voltage is applied to a capacitor, electrons accumulate on one plate, while an equal number of electrons are repelled from the other plate, creating an electric field between them. The capacitance of a capacitor is a measure of its ability to store electrical charge, and it depends on the area of the plates, the distance between them, and the type of dielectric material used.

How it works:

Note* The Red dotted line in this schematic just represents a wire that you will remove and replace later. *

Look closely at the electrolytic capacitors. Be sure to note the stripe and the short leg that marks the polarity. Build your first circuit for this experiment with a 2.2 uF capacitor.


When you build it, consider and reflect on what happens in your circuit as you push the button then let go.


*Extra Experiment: Place the 1000uF capacitor back into its original position. Now replace the normally open push button (PBNO) with the normally closed push button (PBNC). Describe the action of this circuit.*