Question

A boy weighing 40 kg climbs up a vertical height of 200 m. Calculate the amount of
work done by him. How much potential energy does he gain? ( g = 9.8 m /s2
).

Answer 1

Given

• Mass = 40 kg
• Height = 200 m
• Gravitational Acceleration = 9.8 m/s²

To Find

• Work done
• Potential Energy

Solution

● F = ma

● Work = Force × Displacement

● Potential Energy = mgh

✭ Force Applied :

→ F = ma

→ F = 40 × 9.8

→ F = 392 N

✭ Work Done :

→ Work = Force × Displacement

→ Work = 392 × 200

→ Work = 78400 J

or

→ Work = 78400/1000

→ Work = 78.4 KJ

━━━━━━━━━━━━━━━━━━━━━━

✭ Potential Energy :

→ Potential Energy = mgh

→ Potential Energy = 40 × 9.8 × 200

→ Potential Energy = 78400 J

• Work Done = Potential Energy gained

Answer 2

Answer:

49 KJ

Explanation:

We have :mass, m = 50 kgg = 9.8 m/s2Height, h = 100 mNow, gain in potential energy = mgh = 50 × 9.8 × 100 = 49000 J = 49 KJWe have :mass, m = 50 kgg = 9.8 m/s2Height, h = 100 mNow, gain in potential energy = mgh = 50 × 9.8 × 100 = 49000 J = 49 KJ