Advertisements
Advertisements
प्रश्न
What is the change in momentum of a car weighing 1500 kg when its speed increases from 36 km/h to 72 km/h uniformly ?
Advertisements
उत्तर
We know that :
Momentum = mass × velocity
= m × v
Here, mass, m = 1500 kg
And, velocity, v = 36 km/h
= `36 xx 1000/3600`
= `36 xx 1000/3600`
= `36 xx 10/36`
= 10 m/s
Putting these values in the above formula, we get:
Initial Momentum = 1500 × 10 kg.m/s = 15000 kg.m/s
Also, we know that:
Momentum = mass × velocity
= m × v
Here, mass, m = 1500 kg
And, velocity, v = 72 km/h
= `72 xx 1000/3600`
= `72 xx 1000/3600`
= `72 xx 10/36`
= 20 m/s
Putting these values in the above formula, we get:
Final Momentum = 1500 × 20 kg.m/s = 30000 kg.m/s.
The change in momentum of a car weighing 1500 kg when its speed increases from 36 km/h to 72 km/h = 30000 kg.m/s − 15000 kg.m/s = 15000 kg.m/s.
APPEARS IN
संबंधित प्रश्न
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.
Two billiard balls, each of mass 0.05 kg, moving in opposite directions with speed 6 ms-1collide and rebound with the same speed. What is the impulse imparted to each ball due to the other?
Name the physical quantity whose unit is kg.m/s.
Explain why, it is easier to stop a tennis ball than a cricket ball moving with the same speed.
Explain the meaning of the following equation : .
p = m x v
where symbols have their usual meanings.
Fill in the following blanks with suitable words :
Momentum is a _____________ quantity. Its unit is _____________.
Discuss the conservation of momentum in each of the following cases :
(i) a rocket taking off from ground.
(ii) flying of a jet aeroplane.
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.
Two billiard balls A and B, each of mass 50 g and moving in opposite directions with speed of 5 ms–1 each, collide and rebound with the same speed. If the collision lasts for 10–3 s, which of the following statements are true?
- The impulse imparted to each ball is 0.25 kg ms–1 and the force on each ball is 250 N.
- The impulse imparted to each ball is 0.25 kg ms–1 and the force exerted on each ball is 25 × 10–5 N.
- The impulse imparted to each ball is 0.5 Ns.
- The impulse and the force on each ball are equal in magnitude and opposite in direction.
A girl riding a bicycle along a straight road with a speed of 5 ms–1 throws a stone of mass 0.5 kg which has a speed of 15 ms–1 with respect to the ground along her direction of motion. The mass of the girl and bicycle is 50 kg. Does the speed of the bicycle change after the stone is thrown? What is the change in speed, if so?
