Advertisements
Advertisements
प्रश्न
Two bodies of equal masses are moving with uniform velocities v and 2v. Find the ratio of their kinetic energies.
Advertisements
उत्तर
K.E = `1/2 mv^2`
K.E = `1/2 m (2v)^2`
K.E = `(1/2 mv^2) xx 4`
∴ Ratio of their K.E = `(1/2 mv^2)/(4(1/2 mv^2))`
= `1/4`
= 1 : 4
Ratio of K.E. of A and B is 1 : 4.
APPEARS IN
संबंधित प्रश्न
Write an expression for the kinetic energy of an object.
The energy of a flying kite is kinetic energy.
Kinetic energy = 1/2 × mass × ............
Write the expression for the kinetic energy of a body explaining the meaning of the symbols used.
If the speed of a car is halved, how does its kinetic energy change?
A bullet of mass 50 g is moving with a velocity of 500 m s−1. It penetrated 10 cm into a still target and comes to rest. Calculate:
- the kinetic energy possessed by the bullet, and
- the average retarding force offered by the target.
A body of mass 10 kg is moving with a velocity 20 m s-1. If the mass of the body is doubled and its velocity is halved, find:
- the initial kinetic energy, and
- the final kinetic energy.
A truck weighing 1000 kgf changes its speed from 36 km h-1 to 72 km h-1 in 2 minutes. Calculate:
- the work done by the engine and
- its power (g = 10 m s-2)
An apple falling from a tree is an example for kinetic energy.
The kinetic energy of a given body depends on the ______.
