A uniform rod of length L and mass m is held vertically on a rough surface. It is slightly disturbed so that it starts falling. Assuming that friction is sufficiently large so that the end A does not slip, find the angle the rod makes with the vertical when end A looses contact with the ground.
Q5. A Block of mass 6 kg is kept pressed against a rough vertical with coefficient of friction equal to 0.6 by an external horizontal force acting normally (perpendicular) to the plane of the wall of magnitude 100 Newtons. Now, as the block is at rest an additional force of magnitude 45 Newtons is applied horizontally to the block such that this additional force acts tangentially (parallel) to the surface of the wall. The block is observed to start sliding at an acceleration of ? g = 10 m/s2
(1) 2 m/s2 (2) m/s2
(3) m/s2 (4) m/s2
Q3. A block of mass m is held at rest on a smooth horizontal floor. A light frictionless, small pulley is fixed at a height of 6 m from the floor. A light inextensible string of length 16m, connected with A passes over the pulley and another identical block B is hung from the string. Initial height of B is 5 m from the floor as shown in fig. When the system is released from rest. B starts to move vertically downwards and A slides on the floor towards right. (Neglect the radius of the pulley in comparison to the length of the string and take g = 10 m/s2 ). The velocity with which B strikes the ground is ?
1. A frictionless of pulley of negligible weight is suspended from a spring balance. Masses of 1 kg and 5 kg are tied to the two ends of a string which passes the pulley. The masses move due to gravity. During motion, the reading of the spring balance will be :
A uniform rod of length L and mass m is held vertically on a rough surface. It is slightly disturbed so that it starts falling. Assuming that friction is sufficiently large so that the end A does not slip, find the angle the rod makes with the vertical when end A looses contact with the ground.
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Correct answerIt should be a straight inclined line because the acceleration is constant.
Give reason for your answer.
Radius of disc is 8cm. Initially the centre of coin is ? cm away from the centre of the disc. At what minimum frequency will it start slipping from there? By what factor will the answer change if the coin is almost at the rim? (Use g =?? m/s?)