An athlete runs some distance before taking a long jump because

momentum gives a measure of

\(N \quad kg^{-1}\)  is a unit of

A block of mass M is pulled with a force F along a smooth horizontal surface with a rope of mass m. The acceleration of the block will be

A train drop of mass 0.1g is falling with uniform speed of \(10 cm^{-1}\) What is the net force acting on the drop?

State Newton's three laws of motion.

Define the term inertia, what are the different types of inertia?

On what factor does the inertia of a body depend; explain with the help of a suitable example.

A truck starts from rest and rolls down a hill with a constant acceleration. It travels a distance of 400 m in 20 s. Find its acceleration. Find the force acting on if its mass is 7 tonnes.

A stone of 1 kg is thrown with a velocity of \(20 {m}{s}^{-1}\) across the frozen surface of a lake and comes to rest after traveling a distance of 50 m. What is the force of friction between the stone and the ice?

Newton third law of motion deals with the relation between the forces themselves. When a body exerts a force on another body, the other body also exerts a force on the first. When a porter carries a heavy load on his head, the load pushes down on his head. The proter's head pushes the load up. These forces are equal in magnitude. Third law of motion shows that a single force can never exist. The forces always exist in pairs. The two opposing forces are known as action and reaction forces. But the forces of action and reaction always acts on two different bodies.
(a) State Newton third law of motion.
(b) Do action and reaction act on the same body or on different bodies?
(c) Since action and reaction forces are always equal in magnitude. How can any body ever be accelerated?
(d) A gun recoils on firing. Why?

A bullet of mass 20 g moving with a speed of \(500 m {s}^{-1}\) strikes a wooden block of mass 1 kg and gets embedded in it. Find the speed with which block moves along with the bullet.

A body of mass 2 kg, initially moving with a velocity of \(10 m {s}^{-1}\)collides with another body of mass 5 kg at rest. After collision velocity of ifrst bdy becomes \(1 m {s}^{-1}\) .Find the velocity of the second body.

A boy of mass 60 kg running at 3 m/s jumps on to a of mass 140 kg moving with a velocity of 1.5 m/s in the same direction. what is their common velocity?

How much momentum will a dumb-bell of mass 10 kg transfer to the floor if it falls from a height of 80 cm? Take its downward acceleration to be 10 m s^–2.

A motorcar of mass 1,200 kg is moving along a straight line with velocity of 90 km/h. Its velocity is slowed down to 18 km.h s by an unbalanced external force. Calculate the acceleration and change in momentum. Also, calculate the magnitude of the force required.

A large truck and a car, both moving with a velocity of magnitude v, have a head on collision and both of them come to a halt after that. If the collision late for 1 s:
(a) which vehicle experiences the greater force of impact?
(b) Which vehicle experiences the greater change in momentum?
(c) Which vehicle experiences the greater acceleration?
(d) Why is the car likely to suffer more damage than the truck?

State Newton's first law of motion. Explain it with the help of suitable examples.

(a) Express Newton's second law mathematically explaining the symbols used.
(b) Define SI unit of force from this expression.