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प्रश्न
A man spends 7.4 kJ energy in displacing a body by 74 m in the direction in which he applies force, in 2.5 s. Calculate the power spent (in H.P) by the man.
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उत्तर
Power spent = `"work done"/"time taken"`
P = `(7.4 xx 10^3)/2.5`
P = 2960 W
∴ 1 H.P = 746 W
∴ 1 W = `1/746` HP
∴ 2960 W = `2960/746`HP
∴ 2960 W = 3.97 HP
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