Physics
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).
Answer
Given,
Mass = 50 kg
h1 = 0 m
h2 = 15 m
(i) Work done by man = mgh2
Substituting the values we get,
W = 50 x 9.8 x 15 = 7350 J
(ii) Increase in his potential energy = Mg (h2 – h1)
= 50 x 9.8 x (15 - 0)
= 7350 J#### Question 8 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).
Answer
Given,
Mass = 50 kg
h1 = 0 m
h2 = 15 m
(i) Work done by man = mgh2
Substituting the values we get,
W = 50 x 9.8 x 15 = 7350 J
(ii) Increase in his potential energy = Mg (h2 – h1)
= 50 x 9.8 x (15 - 0)
= 7350 J
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