Advertisements
Advertisements
प्रश्न
What do you understand by the kinetic energy of a body?
Advertisements
उत्तर
Kinetic energy is the energy that a body possesses because of its motion. It is directly proportional to the mass and the square of the velocity of the moving body.
K.E = `1/2 m v^2`
APPEARS IN
संबंधित प्रश्न
The kinetic energy of an object of mass m moving with a velocity of 5 m s−1 is 25 J. What will be its kinetic energy when its velocity is doubled? What will be its kinetic energy when its velocity is increased three times?
The energy of a flying kite is kinetic energy.
Define the term kinetic energy. Give one example of a body which possesses kinetic energy.
Two toy-cars A and Bof masses 200 g and 500 g respectively are moving with the same speed. Which of the two has greater kinetic energy?
A cyclist doubles his speed. How will his kinetic energy change: increase, decrease or remain same?
A ball of mass M is moving with a speed v. What is its kinetic energy?
A cannon ball of mass 500 g is fired with a speed of 15 m s-1. Find:
- its kinetic energy.
- its momentum.
A body of mass 60 kg has the momentum 3000 kg m s-1. Calculate:
- the kinetic energy.
- the speed of the body.
Write an expression for the kinetic energy of a body of mass m moving with a velocity v.
Two objects having equal masses are moving with uniform velocities of 2 m/s and 6 m/s respectively. Calculate the ratio of their kinetic energies.
On a level road, a scooterist applies brakes to slow down from a speed of 10 m/s to 5 m/s. If the mass of the scooterist and the scooter be 150 kg, calculate the work done by the brakes. (Neglect air resistance and friction)
When a ball is thrown inside a moving bus, does its kinetic energy depend on the speed of the bus? Explain.
A car is accelerated on a levelled road and attains a speed of 4 times its initial speed. In this process, the kinetic energy of the car :
Which of the following does not posses the ability to do work not because of motion?
A body starts from rest and is acted on by a constant force. The ratio of kinetic energy gained by it in the first five seconds to that gained in the next five-second 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.
When a bell fixed on a cycle rings, then the energy conversion that takes place is ______.
Find the kinetic energy of a body of mass 5 kg moving with a uniform velocity of 10 m s-1.
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.
