A resistor develops 500 J of thermal energy in 20 s when a current of 1.5A is passed through it. If the current is increased from 1.5A to 3A, what will be the energy developed in 20 s.
Solution
${H_1} = i_1^2R\Delta t$<br><br>${H_2} = i_2^2R\Delta t$<br><br>$\Rightarrow {{{H_1}} \over {{H_2}}} = {{i_1^2} \over {i_2^2}}$<br><br>$\Rightarrow {{500} \over {{H_2}}} = {\left( {{1 \over 2}} \right)^2}$<br><br>$\Rightarrow {H_2} = 2000J$
About this question
Subject: Physics · Chapter: Current Electricity · Topic: Electrical Power
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