Chapter 5 – Laws of Motion

A body of mass 40 kg wants to climb up a rope hanging vertically. The rope can withstands a maximum tension of 500 N. What is the maximum acceleration with which the boy can climb rope? Take g=10m/s^2 A body of mass 40 kg wants to climb up a rope hanging vertically. The rope can [...]

A mass of 1kg is suspended by means of a thread. The system is (i) lifted up with an acceleration of 4.9ms^−1 . (ii) lowered with an acceleration of 4.9ms^−2 . The ratio of tension in the first and second case is A block of mass m starting from rest slides down a smooth inclined [...]

A man sits on a chair supported by a rope passing over a frictionless fixed pulley. The man who weighs 1000 N exerts a force of 450 N on the chair downwards while pulling on the rope. If the chair weighs 250 N and g is 10ms^−2, then the acceleration of the chair is A [...]

A person in an elevator accelerating upwards with an acceleration of 2 ms^−2 , tosses a coin vertically upwards with a speed of 20 ms^−1 . After how much time will the coin fall back into his hand? (Take g=10ms^−2) A person in an elevator accelerating upwards with an acceleration of 2 ms^−2 tosses a [...]

A boy of mass 40 kg is climbing a vertical pole at a constant speed. If the coefficient of friction between his palms and the pole is 0.8 and g=10m/s^2, the horizontal force that he is applying on the pole is A boy of mass 40 kg is climbing a vertical pole at a constant [...]

A block of mass m starting from rest slides down a smooth inclined plane of gradient θ, fixed in a lift moving upwards with an acceleration a0 as shown in figure. If the base of the inclined plane has length L, the time taken by the block to slide from top to bottom of the [...]

Two blocks of masses 2 kg and 4 kg are attached by an inextensible light string as shown in the figure. If a force of 120 N pulls the blocks vertically upward, the tension in the string is (take g = 10ms^−2) the tension in the string is (take g = 10ms^−2) Two blocks of [...]

A block is moving on an inclined plane making an angle 45 degree with the horizontal and the coefficient of friction is μ. The force required to just push it up the inclined plane is 3 times the force required to just prevent it from sliding down. If we define N=10μ, then N is A [...]

Two blocks of masses M1​=4 kg and M2​=6 kg are connected by a string of negligible mass passing over a frictionless pulley as shown in the figure below. The coefficient of friction between the block M1​ and the horizontal surface is 0.4. When the system is released the masses M1​ and M2​ start accelerating. What [...]

A wooden block of mass M resting on a rough horizontal surface is pulled with a force F at an angle θ to the horizontal. If μ is coefficient of kinetic friction between the block and the surface, the acceleration of the block is A wooden block of mass M resting on a rough horizontal [...]