### Short Circuits Virtual Lab

A short circuit is a circuit that includes no resistance. Short circuits are dangerous, but also very interesting, and sometimes counterintuitive. To learn about short circuits, we are going to build some short circuits using a simulation. No one will get hurt, and we'll learn a little about how short circuits work.

This is a version of the Series and Parallel Circuits lab conducted virtually, using the simulation below. I recommend you select "intro" mode, although you can use either "intro" mode or "lab" mode.

Simulation provided by PHET interactive simulations at the University of Colorado at Boulder

#### Virtual Materials

• A single battery
• A single light bulb
• Several wires

#### Procedure

1. Put the battery in the holder and connect one end of the battery to the other, without including any light bulb in between, only a wire:

This is a short circuit! Short circuits are dangerous. How does the simulation represent this?
2. Is there electric current running in your short circuit? Is it a high or a low current?
3. Short circuits are dangerous because, with no resistance, there is a very high amount of current! Remember, $$V = IR$$ and $$I = \frac{V}{R}$$, so if $$R$$ is very low, then $$I$$ is very high. People often believe that high voltage is very dangerous, but it is actually high current that tends to make danger. When there is high current is when you start to feel your circuit get warm. In fact, most household items can take only about 15 amps before they break.
Look at the voltage of your battery. If the wire provides only 0.1 Ohms of resistance, find the current and power of your circuit with the formula $$V = IR$$ and $$P = IV$$ Do you think this is safe?
4. Shorting a Light Bulb: Connect a light bulb to a battery so that it lights: