A boy sitting on the topmost berth in the compartment of a train which is just going to stop on a railway station, drops an apple aiming at the open hand of his brother sitting vertically below his hands at a distance of about 2 meter. The apple will fall
Newton's first law of motion describes the following
A person sitting in an open car moving at constant velocity throws a ball vertically up into air. The ball falls
A bird weighs 2 kg and is inside a closed cage of 1 kg. If it starts flying, then what is the weight of the bird and cage assembly
A particle is moving with a constant speed along a straight line path. A force is not required to
If a bullet of mass 5 gm moving with velocity 100 m /sec, penetrates the wooden block up to 6 cm. Then the average force imposed by the bullet on the block is
A force of 100 dynes acts on mass of 5 gm for 10 sec. The velocity produced is
An object will continue moving uniformly until
A diwali rocket is ejecting 0.05 kg of gases per second at a velocity of 400 m/sec. The accelerating force on the rocket is
A body of mass 2 kg moving on a horizontal surface with an initial velocity of 4 m/sec comes to rest after 2 sec. If one wants to keep this body moving on the same surface with a velocity of 4 m/sec, the force required is
A body of mass 2 kg is hung on a spring balance mounted vertically in a lift. If the lift descends with an acceleration equal to the acceleration due to gravity ‘g’, the reading on the spring balance will be
If the tension in the cable of 1000 kg elevator is 1000 kg weight, the elevator
A man weighing 80 kg is standing in a trolley weighing 320 kg. The trolley is resting on frictionless horizontal rails. If the man starts walking on the trolley with a speed of 1 m / s, then after 4 sec his displacement relative to the ground will be
A force of 5 N acts on a body of weight 9.8 N. What is the acceleration produced in m/sec²
A body of mass 40 gm is moving with a constant velocity of 2 cm/sec on a horizontal frictionless table. The force on the table is
When 1 N force acts on 1 kg body that is able to move freely, the body receives
An object with a mass 10 kg moves at a constant velocity of 10 m/sec. A constant force then acts for 4 second on the object and gives it a speed of 2 m/sec in opposite direction. The acceleration produced in it, is
A machine gun is mounted on a 2000 kg car on a horizontal frictionless surface. At some instant the gun fires bullets of mass 10 gm with a velocity of 500 m/sec with respect to the car. The number of bullets fired per second is ten. The average thrust on the system is
A person is standing in an elevator. In which situation he finds his weight less than actual when
A particle of mass 0.3 kg is subjected to a force F=-kx with k=15 N/m What will be its initial acceleration if it is released from a point 20 cm away from the origin
A block of metal weighing 2 kg is resting on a frictionless plane. It is struck by a jet releasing water at a rate of 1 kg/sec and at a speed of 5 m/sec. The initial acceleration of the block will be
Gravels are dropped on a conveyor belt at the rate of 0.5 kg/sec. The extra force required in newtons to keep the belt moving at 2 m/sec is
A parachutist of weight ‘w’ strikes the ground with his legs fixed and comes to rest with an upward acceleration of magnitude 3 g. Force exerted on him by ground during landing is
At a place where the acceleration due to gravity is 10m sec‾² a force of 5 kg-wt acts on a body of mass 10 kg initially at rest. The velocity of the body after 4 second is
A man is standing on a weighing machine placed in a lift. When stationary his weight is recorded as 40 kg. If the lift is accelerated upwards with an acceleration of 2 m/s² , then the weight recorded in the machine will be (g=10 m/s²)
