JEE — Multiple ChoiceHardQuestion 30268
Question
A block of mass 10 kg is on a rough surface (μₖ = 0.2). A force of 30 N is applied at 30° above horizontal. The acceleration is: (g = 10, sin30°=0.5, cos30°=√3/2≈0.866)
- A1.73 m/s²
- B1.27 m/s²Correct
- C3 m/s²
- D2 m/s²
Correct answer
1.27 m/s²
Explanation
N = mg − F sin30° = 100−15 = 85 N. Friction = 0.2×85 = 17 N. Net F_x = Fcos30°−friction = 30×0.866−17 = 25.98−17 = 8.98 N. a = 8.98/10 ≈ 0.9 m/s².