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

A ball of mass m, moving with a speed 2v0, collides inelastically (e > 0) with an identical ball at rest. Show that

(a) For head-on collision, both the balls move forward.

(b) For a general collision, the angle between the two velocities of scattered balls is less than 90°.

13 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

Let v1 and v2 are velocities of two balls after collision

According to conservation of momentum

2mvo = mv1+ mv2

2vo= v1+v2

and e= v2-v1/2vo

v2=v1+2voe

2v1=2vo-2evo

V1=vo (1-e) since e<1 so ball will move after collision.

b)by principle of conservation of linear momentum

P=P1+P2

...Read more

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This is a multiple choice answer as classified in NCERT Exemplar

(c) When M1 comes in contact with the spring. M1 is retarded by the spring force and M2 is accelerated by the spring force. 
 
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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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(b) conserving energy between “O” ans ”A”

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0+1/2mv2= mgh + 1/2mv’

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

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1/2m(v1)2=1/4m(v’)2=1/4m[v2-2gh]

V1= v 2 2 - g h ………….2

From eqn 1 and 2

v ' v 1 = v 2 - 2 g h v 2 - 2 g h / 2 = 2

So v1 = v’/

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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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