Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
Mass of ball = 0.5 kg
Initial velocity = 10 m s−1
Final velocity = 6 m s−1
∴ Initial K.E. = `1/2 mv^2`
= `1/2 xx 0.5 xx 10 xx 10`
= 25 J
Final K.E. = `1/2 mv^2`
= `1/2 xx 0.5 xx 6 xx 6`
= 9 J
Change in K.E. = 25 – 9 = 16 J
∴ K.E. decreases by 4 J
∴ The change in the kinetic energy of the ball is 16 J.
APPEARS IN
संबंधित प्रश्न
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?
When an arrow is shot from a bow, it has kinetic energy in it. Explain briefly from where does it get its kinetic energy?
A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?
Which would have a greater effect on the kinetic energy of an object : doubling the mass or doubling the velocity?
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?
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 :
Derive the formula for the kinetic energy of an object of mass m, moving with velocity v.
Find out the form of energy possessed by the following thing.
Water falls
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:
When a bell fixed on a cycle rings, then the energy conversion that takes place is ______.
