Advertisements
Advertisements
प्रश्न
A car is moving with a speed of 15 km h-1 and another identical car is moving with a speed of 30 km h-1. Compare their kinetic energy.
Advertisements
उत्तर
Two identical cars mean, they have equal mass
K.E = 1/2 mv2
Let m be the mass of each car
Kinetic energy of car A = `1/2` m × `(15)^2` = `225/2` m
= 112.5 m J
Kinetic energy of car B = 1/2 M (30)2
=450 M J
`(K.E. of A) /(K.E. of B)` = `(225 m )/(2 × 450 m )` = `1/4` = 1 : 4
K.E. of car B is 4 times K.E. of car A.
APPEARS IN
संबंधित प्रश्न
Define the term kinetic energy. Give one example of a body which possesses kinetic energy.
Two bodies of equal masses are moving with uniform velocities v and 2v. Find the ratio of their kinetic energies.
A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?
Find the momentum of a body of mass 100 g having a kinetic energy of 20 J.
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.
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?
When a ball is thrown inside a moving bus, does its kinetic energy depend on the speed of the bus? Explain.
What are the uses of mechanical energy?
Explain the types of mechanical energy.
Find the kinetic energy of a body of mass 5 kg moving with a uniform velocity of 10 m s-1.
