A man uses a rope to vertically lower an initially stationary block of mass M at a constant downward acceleration of g/4. Let the block has fallen through a distance `y'.
Question 31: The work done by the tension in the rope on the block is given by
Answer: (a)
Question 32: The final value of kinetic energy of the block is
Answer: (c)2Mgy
Question 33: Final speed of motion of block is
Answer: (c)
A small particle of mass m is released from a height H on a smooth curved inclined surface, which ends into a vertical loop of radius R as shown in adjoining Fig. The initial velocity of particle was zero.
Question 34: Choose the correct statement if value of H = 2R.
Answer: (d) The particle breaks off at a height R < h < 2R
An object of mass 2 kg is lying at rest on a smooth floor. When a force F is applied on it, the object begins to move in the direction of force applied. The force is a variable force. Variation of force F with distance covered by the object has been shown in adjoining figure.
Question 35: The maximum kinetic energy of the object is
Answer: (c) 17.5 J
Question 36: At s = 7 m
Answer: (b) K.E. of the object is positive
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