Theory & SafetyPregunta 108 de 120
How much power is dissipated when 5 amperes flows through a 20-ohm resistor?
a.100 watts
b.500 watts
c.4 watts
d.2,000 watts
Explicación
Using P = I squared x R, the calculation is 5 x 5 x 20 = 500 watts. The 100-watt answer multiplies current by resistance without squaring the current, 4 watts divides the wrong way, and 2,000 watts squares the resistance instead of the current.
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