Question

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: (i) the force applied and (ii) the power spent (in H.P) by the man.

April 8, 2024

Answer

Work done = 7.4 kJ = 7400 J

Displacement (S) = 74 m

Time (t) = 2.5 s

(i) W = F x S

Force = $work\over distance$

= $7400\over 74$

= 100 N

(ii) Power spent = $7400\over 2.5$

Power = 2960 W

We know,

746 W = 1 HP

∴ 2960 W = $2960\over 746$ = 3.97 HP

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