Per NCERT Example 7.10, a weightlifter lifts a 75 kg mass by 2 m in 5 seconds (taking g = 10 m/s²). What POWER does she require?
A75 W
B150 W
C300 W (= 1500 J / 5 s)
D1500 W
Answer & Solution
Correct answer: C. 300 W (= 1500 J / 5 s)
Per NCERT Example 7.10, W = mgh = 75 × 10 × 2 = 1500 J. P = W/t = 1500 / 5 = 300 W.
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