Goals: What causes static electricity? What are two ways to prevent circuits from having too much current?

Q: What happens when a circuit has too much power? When the resistance of a circuit is too low, the wires carry too much current. When this happens, the circuit is said to be overloaded. Circuits can be overloaded when too many appliances are plugged into a single power source.

Q: What happens when a circuit has too much power? There are two ways to prevent overloading circuits: 1) Fuse A fuse is an electrical device contains a metal strip that melts (thus opening the circuit) when the current in a circuit becomes too great. Once the metal strip inside a fuse melts, it must be replaced.

Q: What happens when a circuit has too much power? There are two ways to prevent overloading circuits: 2) Circuit breaker A circuit breaker is a device that protects a circuit from current overloads by opening the circuit when the current becomes too great. Circuit breaker act like switches and can be reset to close the circuit again.

Q: What is a short circuit? Caused by improper wiring. The current travels around the resistor, therefore (often) overloading the circuit.

Q: Why do we shock people? When you walk across the floor, electric charges are moving from the floor through your body, causing an excess of electrons in your body.

Q: Why do we shock people? When you come in contact with something that doesn’t have an excess of charge, the charges move from your body to the other thing. Called static electricity. “Static”- means unmoving. The electrons just hang out in your body for a while.

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