Advertisements
Advertisements
प्रश्न
If an object has 0 momentum, does it have kinetic energy? Explain your answer.
Advertisements
उत्तर
Momentum of an object, P = mv
If P = 0
⇒ `"v" = 0`
This is because the mass of the object can never be 0.
Now, the kinetic energy of the object, `"K" = 1/2 xx "m" xx "v"^2`
Since, v = 0
⇒ K = 0
Hence, when the object has zero momentum, its kinetic energy is also zero.
APPEARS IN
संबंधित प्रश्न
Write an expression for the kinetic energy of an object.
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?
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?
The energy of a flying kite is kinetic energy.
Define the term kinetic energy. Give one example of a body which possesses kinetic energy.
A cyclist doubles his speed. How will his kinetic energy change: increase, decrease or remain same?
If the speed of a body is halved, what will be the change in its kinetic energy?
What is the kinetic energy of a body of mass 1 kg moving with a speed of 2 m/s?
A ball of mass 200 g falls from a height of 5 metres. What is its kinetic energy when it just reaches the ground? (g = 9.8 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?
A bullet of mass 15 g has a speed of 400 m/s. What is its kinetic energy? If the bullet strikes a thick target and is brought to rest in 2 cm, calculate the average net force acting on the bullet. What happens to the kinetic energy originally in the bullet?
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 :
Derive the formula for the kinetic energy of an object of mass m, moving with velocity v.
Water stored in water dams possesses kinetic energy.
When the speed of a moving object is doubled, then its kenetic energy ______.
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.
