A meter stick of mass 400 g is pivoted at one end and displaced through an angle 60°. The increase in its potential energy is
Options
(a) 2 J
(b) 3 J
(c) 0 J
(d) 1 J
Correct Answer:
1 J
Explanation:
Change in potential energy = mg/(1/2) (1-cosθ)
Given: mass = 400g = 0.4 kg and angle = 60°
Therefore, ∆U = 0.4 × 10 × (1/2) × (1-cos 60°) = 1 J.