Ampere, or amps for short, is a measuring unit of electrical current. It is defined as one coulomb of charge moving through a point in a second. 1 coulomb is roughly equal to a charge of 6.242X10^18 protons.

The value of ampere can be realized in association of Ohm's law, where amperes can be obtained by deviding wattage by voltage.

Everyday examples:

USB charging cable typically takes 10.5 W at 5.0 V, or 2.1 A

Typical car has a 12V battery. Various accessories powered by this battery might include:

Instrument panel light using 2 W adn 166 mA.

Headlight using 60 W at 5 A.

Starter motor using 1-2 kW at 80-160 A.

North American power outlets supply 120 V. Typical circuit breaker provides a maximum of 15 or 20 A of current to a given outlet. 22 inch portable TV using 35 W at 290 mA. Tungsten light bulb using 60-100 W at 500-830 mA. Toaster or kettle using 1.5 kW at 12.5 A. Hair dryer using 1.8 kW at 15 A. USB cell phone charger using 10W at 83 mA.

European domestic power supplies provide electricity at 230 V, so for the same amount of power, a particular appliance would need a smaller current. With the formula for Power been P = I X V, so it follows that if the voltage doubled and the power remains the same, the current will be halved. Typical circuit breakers will provide 16 A. Some typical appliances would be: TV using 35 W at 145-150 mA, tungsten light bulb using 60 - 100 W at 240-450 mA, compact flourescent lamp using 10-30 W at 56-112 mA, toaster or kettle using 2 kW at 9 A, immersion heater using 4.6 kW at 19-20 A.

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