Question 3
MotionA 5 kg block is released from rest on a smooth plane inclined at an angle of 30° to the horizontal. What is the acceleration down the plane? [g = 10 m s−2]
- A.5.0 m s−2
- B.5.8 m s−2
- C.8.7 m s−2
- D.25.0 m s−2
Show the answer and explanation
Answer: A (5.0 m s−2)
Explanation
On a smooth slope only the component of weight along the slope acts, so a = g sin 30° = 10 × 0.5 = 5.0 m s−2.