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Work, Energy, and PowerClass 11thPhysics NCERT Exemplar Solutions Class 11th Chapter Sixphysics ncert solutions class 11thPhysics

In an elastic collision of two billiard balls, which of the following quantities remain conserved during the short time of collision of the balls (i.e., when they are in contact).

(a) Kinetic energy.

(b) Total linear momentum?

 Give reason for your answer in each case.

2 Views|Posted 8 months ago
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1 Answer
P
8 months ago

This is a short answer type question as classified in NCERT Exemplar

Total linear momentum of the system of two balls is always conserved. While balls are in contact, there may be deformation which means elastic PE which came from part of KE .But they are in contact while collision so according to ab

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This is a multiple choice answer as classified in NCERT Exemplar

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A bullet of mass m fired at 30° to the horizontal leaves the barrel of the gun with a velocity v. The bullet hits a soft target at a height h above the ground while it is moving downward and emerges out with half the kinetic energy it had before hitting the target. Which of the following statements are correct in respect of bullet after it emerges out of the target?

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This is a multiple choice answer as classified in NCERT Exemplar

(b) conserving energy between “O” ans ”A”

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( v ' ) 2 2 = v 2 2 = - g h

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1/2m(v1)2=1/4m(v’)2=1/4m[v2-2gh]

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From eqn 1 and 2

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Payal Gupta

This is a multiple choice answer as classified in NCERT Exemplar

(c) m =150g =3/20kg

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Physics NCERT Exemplar Solutions Class 11th Chapter Six 2025

Physics NCERT Exemplar Solutions Class 11th Chapter Six 2025

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