Advertisements
Advertisements
प्रश्न
A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?
Advertisements
उत्तर १
Kinetic energy of the body changes to potential energy when it is thrown vertically upwards and its velocity becomes zero.
उत्तर २
When a body is thrown vertically upwards against the force of gravity, its kinetic energy keeps on decreasing as its velocity decreases. At the maximum height, kinetic energy becomes zero, as the velocity of the body becomes zero at this moment. The kinetic energy of the body is completely transformed into potential energy at the maximum height.
संबंधित प्रश्न
What is the kinetic energy of an object?
An object of mass, m is moving with a constant velocity, v. How much work should be done on the object in order to bring the object to rest?
Calculate the work required to be done to stop a car of 1500 kg moving at a velocity of 60 km/h?
A freely falling object eventually stops on reaching the ground. What happens to its kinetic energy?
Name the unit of physical quantity obtained by the formula `(2K)/v^2` Where K: kinetic energy, v: linear velocity
Write the expression for the kinetic energy of a body explaining the meaning of the symbols used.
The kinetic energy of a body is the energy by virtue of its ______.
Two bodies of equal masses are moving with uniform velocities v and 2v. Find the ratio of their kinetic energies.
A bullet of mass 50 g is moving with a velocity of 500 m s−1. It penetrated 10 cm into a still target and comes to rest. Calculate:
- the kinetic energy possessed by the bullet, and
- the average retarding force offered by the target.
A truck weighing 1000 kgf changes its speed from 36 km h-1 to 72 km h-1 in 2 minutes. Calculate:
- the work done by the engine and
- its power (g = 10 m s-2)
A man drops a 10 kg rock from the top of a 5 m ladder. What is its speed just before it hits the ground? What is its kinetic energy when it reaches the ground? (g = 10 m/s2)
A horse and a dog are running with the same speed. If the weight of the horse is ten times that of the dog, What is the ration of their kinetic energies?
The momentum of a bullet of mass 20 g fired from a gun is 10 kg.m/s. The kinetic energy of this bullet in kJ will be :
Explain the difference between potential energy and kinetic energy.
What are the uses of mechanical energy?
The energy possessed by a cricket ball bowled by a player is ______.
A car of mass 120 kg is moving at a speed 18 km/h and it accelerates to attain a speed of 54 km/h in 5 seconds. Calculate:
- the work done by the engine.
- the power of the engine.
If the mass as well as the velocity of a body is doubled then the kinetic energy of the body ______ the initial kinetic energy.
A ball of mass 0.5 kg slows down from a speed of 10 m s−1 to that of 6 m s−1. Calculate the change in the kinetic energy of the ball.
