JEE Mains · Physics · STD 12 - 3. current electricity
Water fall from a \(40\,m\) high dam at the rate of \(9 \times 10^{4}\,kg\) per \(hour\). Fifty percentage of gravitational potential energy can be converted into electrical energy. Using this hydroelectric energy number of \(100\,W\) lamps, that can be lit, is (Take \(\left.g=10\,ms ^{-2}\right)\)
- A \(25\)
- B \(50\)
- C \(100\)
- D \(18\)
Answer & Solution
Correct Answer
(B) \(50\)
Step-by-step Solution
Detailed explanation
\(\frac{9 \times 10^{4} \times g \times 40}{3600} \times 0.5= n \times 100\) \(\frac{10^{4} \times 0.5}{100}= n\) \(100 \times 0.5= n\) \(n =50\)
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