Electricity powers lights, phones, appliances, heaters, and many tools we use every day, but it must be handled with care. At home, electrical hazards can lead to shocks, burns, fires, or damaged equipment if wiring and devices are misused. Learning basic electrical safety helps students protect themselves, their families, and their homes.
Emergency preparedness also means knowing what to do before a problem becomes dangerous.
Key Facts
- Ohm's law: V = IR, where voltage equals current times resistance.
- Electrical power: P = IV, where power equals current times voltage.
- Current as low as 0.01 A through the body can be painful, and higher currents can be life threatening.
- Water lowers the body's resistance, so wet hands, sinks, tubs, and outdoor rain increase shock risk.
- A circuit breaker or fuse protects wiring by stopping current when a circuit is overloaded.
- GFCI outlets help prevent severe shock by shutting off power when current leaks to ground.
Vocabulary
- Electric shock
- An electric shock happens when electric current passes through the body.
- Circuit breaker
- A circuit breaker is a safety switch that opens a circuit when too much current flows.
- GFCI
- A ground fault circuit interrupter is a device that quickly cuts power when it detects current leaking from a circuit.
- Overload
- An overload occurs when too many devices draw more current than a circuit is designed to carry.
- Grounding
- Grounding provides a safe path for unwanted electric current to travel into the earth instead of through a person.
Common Mistakes to Avoid
- Using electronics near water, because water and wet skin reduce resistance and make electric shock more likely.
- Plugging many high-power devices into one outlet, because the circuit can overheat and start a fire before a device seems broken.
- Pulling a plug out by the cord, because this can damage the insulation or loosen wires and expose live conductors.
- Touching someone who is being shocked before power is shut off, because your body can become part of the circuit too.
Practice Questions
- 1 A hair dryer uses 12 A from a 120 V outlet. What power does it use in watts?
- 2 A lamp has a resistance of 240 ohms and is connected to a 120 V outlet. What current flows through the lamp?
- 3 A toaster and microwave are plugged into the same power strip, and the cord feels warm. Explain what should be done and why this is a safety issue.