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Question
Calculate the quantity of heat produced in a 20 Ω resistor carrying 2.5 A current in 5 minutes.
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Solution
Given: \[R=20\ \Omega\]
\[I=2.5\text{A}\]
\[t=5\times60=300\ \text{s}\]
Formula: \[H=I^{2}Rt\]
\[H=(2.5)^{2}\times20\times300\]
\[H=(6.25)\times20\times300\]
∴ \[H=37{,}500\ \text{J}\]
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