A 2 kg mass is raised by 3 m. What is the increase in gravitational potential energy?

A 2 kg mass is raised by 3 m. What is the increase in gravitational potential energy?

• A. 58.8 J
• B. 58.0 J
• C. 59.6 J
• D. 60.0 J

Answer: (A)

The change in gravitational potential energy when you lift a mass in a uniform gravitational field is ΔU = m g h. Here, m = 2 kg, g ≈ 9.8 m/s^2, and h = 3 m. So ΔU = 2 × 9.8 × 3 = 58.8 J. This matches the given value. Using a slightly different value of g (like 9.81) would give about 58.86 J, still around 58.8–58.9 J; rounding to 60 J would come from using g = 10 m/s^2.

The change in gravitational potential energy when you lift a mass in a uniform gravitational field is ΔU = m g h. Here, m = 2 kg, g ≈ 9.8 m/s^2, and h = 3 m. So ΔU = 2 × 9.8 × 3 = 58.8 J. This matches the given value. Using a slightly different value of g (like 9.81) would give about 58.86 J, still around 58.8–58.9 J; rounding to 60 J would come from using g = 10 m/s^2.