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Question
Two resistances R and 2R are connected in parallel in an electric circuit. The thermal energy developed in R and 2R are in the ratio _______________ .
Options
1 : 2
2 : 1
1 : 4
4 : 1
Solution
2 : 1
Thermal energy developed in the resistances,
H = \[\frac{V^2}{R}t\]
Heat developed in the resistance R, H1= \[\frac{V^2}{R}t\]
Heat developed in the resistance 2R, H2 = \[\frac{V^2}{2R}t\]
Thus, Heat developed in the resistance R and 2R are in ratio 2 : 1.
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