Eli5 how does playing around with different metrics of amps, ohms, and volts alter how powerful electricity is?

Question

Eli5 how does playing around with different metrics of amps, ohms, and volts alter how powerful electricity is?

In: 9

Answer 1

There’s two main equations for electrical power.

P = I*V, or (Power in Watts) = (Current in Amperes) * (Voltage in Volts)

and V=I*R, or (Voltage in Volts) = (Current in Amps) * (Resistance in Ohms)

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So if you have a basic circuit, the resistance is roughly constant during normal use. And voltage and current are directly dependent on resistance. So lets say you have 9 Volt battery, and you hook it up to a 100 Ohm circuit. V=I*R, you can calculate that the current will be 9V/100Ohm, or .09A or 90mA (milliAmperes). With P= I*V, we get 0.81W.

To get more power, we can increase the voltage, which will increase the current as well. Or we can reduce the resistance, which will increase the current while the voltage stays the same.