COMEDK · Physics · 6. Work Power Energy
One coolie takes \(1\mathrm{min}\) to raise a suitcase through a height of \(2 \mathrm{~m}\) but the second coolie takes \(30 \mathrm{~s}\) to raise the same suitcase to the same height. The powers of two coolies are in the ratio.
- A \(1: 3\)
- B \(2: 1\)
- C \(3: 1\)
- D \(1: 2\)
Answer & Solution
Correct Answer
(D) \(1: 2\)
Step-by-step Solution
Detailed explanation
Here, work done \(=m g h\) As, \(m\) and \(h\) is same, so work done will be same in both cases. Power, \(P=\frac{\text { Work done }(W)}{\text { Time taken }(t)}\) \(\Rightarrow \quad \frac{P_{1}}{P_{2}}=\frac{t_{2}}{t_{1}}=\frac{30}{60}=\frac{1}{2}\) or \(1: 2\)
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