Question

A man of mass 50 kg climbs up a ladder of height 15m. Calculate: (i) the work done by the man, (ii) the increase in his potential energy. (g = 9.8 m s-2).

April 18, 2024

Answer

Mass = 50 kg

h₁ = 0 m

h₂ = 15 m

(i) Work done by man = mgh₂

Substituting the values we get,

W = 50 × 9.8 × 15 = 7350 J

(ii) Increase in his potential energy = Mg (h₂ – h₁)

= 50 × 9.8 × (15 – 0)

= 7350 J

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