NTA Abhyas JEE Main2020PhysicsLaws of MotionPractice
A hanging block of mass m ' prevents the smaller block of mass m from slipping over a movable triangular block of mass M . All the surfaces are frictionless and the strings and the pulleys are light. Value of mass m ' in terms of m , M and θ is
Options
- Am + M cot θ - 1
- Bm - M cot θ + 1
- Cm - M cot θ - 2
- Dm + M cot θ + 2
Correct answer
A. m + M cot θ - 1
Step-by-step solution
Pulling force is m ' g , while mass in motion is m + M + m ' . So acceleration of the system will be given by a = m ' g m + M + m ' ....(i) Mass m will not slide over M if a cosθ = g sinθ ....(ii) From equation (i) in (ii), we get m ′ g cos θ m + M + m ′ = g sin θ or m ′ = m + M cot θ - 1