Question

A boy weighing 50 kgf climbs up from the first floor at a height of 3 m above the ground to the third floor at a height of 9 m above the ground. What will be the increase in his gravitational potential energy?
(Take g = 10 N kg^-1).

April 18, 2024

Answer

Weight (mg) = 50 Kgf = 50 ×10 N

Increase in gravitational potential energy = mg(h₂ – h₁)

= 50 ×10 × (9 – 3)

= 50 × 10 × 6

= 3000 J

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