JEE Mains · Physics · STD 12 - Current electricity
- JEE Mains 2019
- Medium
- Numerical
Two equal resistances when connected in series to a battery, consume electric power of \(60\,W.\) If these resistances are now connected in parallel combination to the same battery, the electric power consumed will be .............. \(W\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) \(240\)
Step-by-step Solution
Detailed explanation
Assuming constant voltage supply
\(P=60=\frac{V^{2}}{R_{1}+R_{2}}\) .......\((1)\)
\( \text { And } P^{\prime}=\frac{V^{2}}{R_{1}}+\frac{V^{2}}{R_{2}}=\frac{2 V^{2}}{R_{1}} =4 P=4 \times 60 \)
\(=240 \,\mathrm{W} \)
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