Advertisements
Advertisements
प्रश्न
If the speed of a car is halved, how does its kinetic energy change?
Advertisements
उत्तर
K.E = `1/2 mv^2`
when `v_1 = 1/2 v`
∴ K.E. = `1/2 mv_1^2`
= `1/2 m (1/2 V)^2`
= `1/2 m v^2 (1/4)`
new K.E = `1/4 K.E`
∴ K.E changes to `1/4 th`
APPEARS IN
संबंधित प्रश्न
Certain force acting on a 20 kg mass changes its velocity from 5 m s-1 to 2 m s-1. Calculate the work done by the force.
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?
Two bodies of equal masses are moving with uniform velocities v and 2v. Find the ratio of their kinetic energies.
A cannon ball of mass 500 g is fired with a speed of 15 m s-1. Find:
- its kinetic energy.
- its momentum.
How much work is needed to be done on a ball of mass 50 g to give it a momentum of 5 kg cm s-1?
A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?
What do you understand by the kinetic energy of a body?
If an object has 0 momentum, does it have kinetic energy? Explain your answer.
The kinetic energy of a given body depends on the ______.
If the mass as well as the velocity of a body is doubled then the kinetic energy of the body ______ the initial kinetic energy.
