Question Detail
Question
A 3-kg crate slides down a 1 m long ramp inclined at 30°. It starts from rest at the top. If the surface is frictionless, what is the speed of the crate at the bottom?
Correct Answer
Option B is the correct answer.
Detailed Explanation
The vertical height of the ramp is h = 1 m × sin 30° = 0.5 m. Initial energy is all potential: mgh. Final energy is all kinetic: ½ mv². So, ½ mv² = mgh, v = √(2gh) = √(2 × 9.8 × 0.5) = √9.8 ≈ 3.13 m/s.
Hint
The height of the ramp is needed. Use conservation of mechanical energy for a frictionless incline.