Torch with a push buttonTinkerPieCircuit tutorial 4 of 24 · Beginner · 10 minutes

Build a torch: a battery, a push button and an LED with a resistor.

Open this circuit in TinkerPieCircuit (free, runs in your browser)

What you will learn

• Push button versus slide switch
• Why the LED needs a resistor
• Wiring parts in series

Parts

1 battery (3 V)1 push button1 resistor, 100 Ω1 LED

Steps

1. Add the parts

   Hide the board, then add Battery, Push button, Resistor and LED. Set the resistor to 100 Ω.

2. Wire in a loop

   Battery + → button → resistor → LED long leg (+). Then the LED short leg (−) → battery −.

3. Try it

   Press ▶ Start. Click and hold the red cap of the button. The LED lights while you hold it.

4. Try a different colour

   Select the LED and pick blue. A blue LED needs about 3 V, so with a 3 V battery it is very dim. Why?

This circuit needs no code. It runs by itself when you open it.

How it works

A push button closes the circuit only while you press it. The resistor limits the current to a safe value so the LED does not burn out.

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