Advertisements
Advertisements
प्रश्न
A ball X of mass 1 kg travelling at 2 m/s has a head-on collision with an identical ball Y at rest. X stops and Y moves off. Calculate the velocity of Y after the collision.
Advertisements
उत्तर
According to the law of conservation of momentum, the two momenta given are equal to each other.
Before collision, momentum of the first ball is = (1)(2) = 2 kg.m/s
Before collision, momentum of the second ball = (1)(0) = 0
After collision, momentum of the first ball = (1)(0) = 0
After collision, momentum of the second ball is = (1)(v)
Now,
2 + 0 = 0 + 1v
⇒ v = 2
The velocity of Y after the collision is 2m/s.
APPEARS IN
संबंधित प्रश्न
From a rifle of mass 4 kg, a bullet of mass 50 g is fired with an initial velocity of 35 m s−1. Calculate the initial recoil velocity of the rifle.
Two objects of masses 100 g and 200 g are moving along the same line and direction with velocities of 2 m s−1 and 1 m s−1, respectively. They collide and after the collision, the first object moves at a velocity of 1.67 m s−1. Determine the velocity of the second object.
Explain why, it is easier to stop a tennis ball than a cricket ball moving with the same speed.
Which physical quantity corresponds to the rate of change of momentum ?
Name the principle on which a rocket works.
Fill in the following blanks with suitable words :
In collisions and explosions, the total _____________ remains constant, provided that no external _____________ acts.
A gun of mass 3 kg fires a bullet of mass 30 g. The bullet takes 0.003 s to move through the barrel of the gun and acquires a velocity of 100 m/s. Calculate:
- the velocity with which the gin recoils.
- the force exerted on gunman due to recoil of the gun
Name the law involved in the following situation :
the sum of products of masses and velocities of two moving bodies before and after their collision remains the same.
A monkey of mass 20 kg rides on a 40 kg trolley moving with constant speed of 8 m/s along a horizontal track If the monkey jumps vertically to grab the overhanging branch of a tree, the speed of the trolley after the monkey has jumped off is ______.
Two blocks P and Q of masses 0.3 kg and 0.4 kg, respectively, are stuck to each other by some weak glue as shown in the figure. They hang together at the end of a spring with a spring constant of k = 200 N/m. The block Q suddenly falls free due to the failure of glue, then the maximum kinetic energy of block P during subsequent motion will be ______ mJ.
