Advertisements
Advertisements
प्रश्न
Two bodies have masses in the ratio 5 : 1 and their kinetic energies are in the ratio 125 : 9. Calculate the ratio of their velocities.
Two bodies A and B have masses in the ratio 5 : 1 and their kinetic energies are in the ratio 125 : 9. Find the ratio of their velocities.
Advertisements
उत्तर
Given `m_A/m_B = 5/1`
`K_A/K_B = 125/9`
Since `K_A/K_B = (1/2 m_A V_A^2)/(1/2 m_B V_B^2)`
= `(m_A/m_B)· V_A^2/V_B^2`
`125/9 = 5/1 ⋅ V_A^2/V_B^2 or V_A/V_B = sqrt(25/9)`
= `5/3`
The ratio of velocities of A and B is 5 : 3.
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.
A ball of mass M is moving with a speed v. What is its kinetic energy?
A body of mass 60 kg has the momentum 3000 kg m s-1. Calculate:
- the kinetic energy.
- the speed of the body.
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?
How does the kinetic energy of a moving body depend on its (i) speed, and (ii) mass?
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 body of 2 kg falls from rest. What will be its kinetic energy during the fall at the end of 2 s? (Assume g = 10 m/s2)
What do you understand by the kinetic energy of a body?
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?
