Concepts Of Physics MCQ Edition [Volume 1]PhysicsFriction
As shown in the figure, the friction coefficient between the board and the floor is . Determine the maximum force the man can exert on the rope so that the board does not slip on the floor.
Options
- A(M+m)g
- BMg 1+
- C(M+m)g 1+
- D(M+m)g 1-
Correct answer
C. (M+m)g 1+
Step-by-step solution
Let T be the tension in the rope, which is equal to the force exerted by the man on the rope. Let us consider the man and the board as a single system. The external forces acting on this system in the vertical direction are: 1. Total weight of the man and the board, (M+m)g , acting downwards. 2. Normal reaction N from the floor, acting upwards. 3. Tension T from the rope pulling the man upwards. For vertical equilibrium of the system, we have: N + T = (M+m)g N = (M+m)g - T In the horizontal direction, the rope pass