Power, Current, and Resistance (P=I²R) | GCSE Physics
Power dissipated as heat in a resistor depends on the square of the current.
Why does doubling current quadruple the power dissipation?
What is Power, Current, and Resistance (P=I²R) | GCSE Physics?
"The power dissipated as heat in a resistor, proportional to the square of the current."
What is the unit of electrical resistance?
Misconception: When a circuit is closed, the 'spent' current returns to the battery.
Calculate the charge flow if a 3A current flows for 10 seconds.
Current is the rate of flow of ____.
Heating Effect
Power (W) = Current² (A) x Resistance (Ω).
Doubling current quadruples the power loss (because $2^2 = 4$).
This formula explains why high-voltage power lines use low current to minimize energy loss.
High resistance components at a fixed current produce more heat.
Advanced Calc: To find Current (I) from Power and Resistance, you must take the SQUARE ROOT of P/R.
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