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प्रश्न
A molecule in a gas container hits a horizontal wall with speed 200 m s–1 and angle 30° with the normal, and rebounds with the same speed. Is momentum conserved in the collision? Is the collision elastic or inelastic?
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उत्तर
Speed of molecule u = 200 m s-1, θ = 30°
Speed after rebound ν = 200 m s-1
∵ Momentum is conserved in every type of collision.
Therefore, momentum will be conserved in this collision also.
kinetic energy of the system when hitting the wall `"K"_1 = 1/2 "m""u"^2`
= `1/2"m" (200)^2 "J"`
kinetic energy after collision `"K"_2 = 1/2 "m""ν"^2`
= `1/2"m" (200)^2 "J"`
∴ The collision is elastic collision.
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संबंधित प्रश्न
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Answer carefully, with reason:
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If the potential energy of two billiard balls depends only on the separation distance between their centres, is the collision elastic or inelastic? (Note, we are talking here of potential energy corresponding to the force during collision, not gravitational potential energy.)
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Which of the following potential energy curves in Fig. cannot possibly describe the elastic collision of two billiard balls? Here r is distance between centres of the balls.
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Answer the following question.
Obtain its value for an elastic collision and a perfectly inelastic collision.
Answer the following question.
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- Colliding bodies are identical.
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- A very light object collides on a comparatively much massive object, initially at rest.
Solve the following problem.
A ball of mass 100 g dropped on the ground from 5 m bounces repeatedly. During every bounce, 64% of the potential energy is converted into kinetic energy. Calculate the following:
- Coefficient of restitution.
- The speed with which the ball comes up from the ground after the third bounce.
- The impulse was given by the ball to the ground during this bounce.
- Average force exerted by the ground if this impact lasts for 250 ms.
- The average pressure exerted by the ball on the ground during this impact if the contact area of the ball is 0.5 cm2.
Arrive at an expression for elastic collision in one dimension and discuss various cases.
A body of mas 'm' moving with speed 3 m/s collides with a body of mass '2m' at rest. The coalesced mass will start to move with a speed of ______.
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A ball of mass m, moving with a speed 2v0, collides inelastically (e > 0) with an identical ball at rest. Show that for a general collision, the angle between the two velocities of scattered balls is less than 90°.
Answer carefully, with reason:
Is the total linear momentum conserved during the short time of an inelastic collision of two balls ?
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What do the objects do "after collision"?
Which of the following real-life scenarios is the best example of a collision as defined in the source?
