NTA Abhyas JEE Main2020PhysicsLaws of MotionPractice
A block of mass 200   kg is being pulled by some men, up an inclined plane of inclination 45 ° and coefficient of friction 0 . 5 , as shown in the figure. If each man can apply a maximum force of 500   N , then the minimum number of men required to just slide the block, up the plane is
Options
- A10
- B7
- C5
- D9
Correct answer
C. 5
Step-by-step solution
Total force required F = m g sin θ + f = m g sin θ + μ s R = m g sin θ + μ s m g cos θ = m g ( sin θ + μ s cos θ ) = 200 ×9.8 ( sin 45 ° + 0.5 cos 45 ° ) F = 200 ×9.8 × 3 2 2 The number of men required will be 200 ×9.8 × 3 (500) × 2 2 = 4.1