Advertisements
Advertisements
प्रश्न
What do you mean by the conservation of momentum? Briefly, explain the collision between two bodies and the conservation of momentum.
Advertisements
उत्तर
Conservation of momentum in case of a collision between two bodies means the total momentum before and after collision remains unchanged or conserved, provided no net force acts on the system.
Consider two bodies A and 8 having masses m1 and m, and initial velocities u1 and u, respectively. The bodies collide head on with each other and their collision lasts for t seconds. Suppose the velocities of A and 8 after collision are v1 and v, respectively. Assume that no external forces are acting on the bodies.
Rate of change of momentum of ball A = m1(v1 - u1)/t .
Rate of change of momentum of ball 8 = m1 (v1 - u1)/t .
If FAB is the force exerted by A on 8 and FBA is the force ex
Rated by 8 on A, we can write
FAB= m1(v1 - u1)/t .
FBA = m1 (v1 - u1)/t .
FAB = -FBA
m1(v1 - u1)/t = - m2(v2- u2)/t .
m1(v1 - u1) = - m2(v2- u2)
m1v1 +m2v2 = m1u1+m2u2
So total momentum after collision = total momentum before collision.
This proves conservation of momentum during collision.
APPEARS IN
संबंधित प्रश्न
An aircraft executes a horizontal loop at a speed of 720 km/h with its wings banked at 15°. What is the radius of the loop?
A monkey of mass 40 kg climbs on a rope in given Figure which can stand a maximum tension of 600 N. In which of the following cases will the rope break: the monkey
(a) climbs up with an acceleration of 6 m s–2
(b) climbs down with an acceleration of 4 m s–2
(c) climbs up with a uniform speed of 5 m s–1
(d) falls down the rope nearly freely under gravity?
(Ignore the mass of the rope).
A block of mass 15 kg is placed on a long trolley. The coefficient of static friction between the block and the trolley is 0.18. The trolley accelerates from rest with 0.5 ms–2 for 20 s and then moves with uniform velocity. Discuss the motion of the block as viewed by (a) a stationary observer on the ground, (b) an observer moving with the trolley.
A block of mass m is placed on a smooth wedge of inclination θ. The whole system is accelerated horizontally so that the block does not slip on the wedge. The force exerted by the wedge on the block has a magnitude.
Both the springs shown in the following figure are unstretched. If the block is displaced by a distance x and released, what will be the initial acceleration?
An empty plastic box of mass m is found to accelerate up at the rate of g/6 when placed deep inside water. How much sand should be put inside the box so that it may accelerate down at the rate of g/6?
The linear momentum of a body of mass m moving with velocity v is :
A pebble is thrown vertically upwards with a speed of 20 m s-1. How high will it be after 2 s? (Take g = 10 m s-2)
Prove mathematically F = ma
What do you mean by an impulsive force?
