Practice question · Numerical answer
A current of 3 amperes flows through a component of resistance 2 ohms. How much power is dissipated as heat, in watts?
Hints
- Power dissipated is the square of the current times the resistance.
- Square the current before multiplying by the resistance.
Show the answer
18
Why
9 times 2 = 18 W. The current is squared, so doubling it would quadruple the heat, the reason a chip's power budget, not its logic, is what caps how fast it can be clocked.
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