Q5 of 42 Page 29

Conservation of momentum in a collision between particles can be understood from

As we know newton 2nd law state that rate of change of momentum is equal to external force applied on anybody or mathematically ext now conservation of momentum mean ext or so

Hence we can understand conservation of momentum by 2nd law so options (a) & (b) are wrongs.


Now let’s look to 3rd law which state that every action has equal and opposite reaction or in another word action force is equal to reaction force in magnitude but opposite in direction.


i.e. we can also write this as




From here the law of conservation of momentum also proved.


Therefore, option (d) is correct.

More from this chapter

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3

A cricket ball of mass 150 g has an initial velocity u = (3î + 4ĵ) m s-1 and a final velocity V = -(3î + 4ĵ) m s-1 after being hit. The change in momentum (final momentum-initial momentum) is (in kg m s1)

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In the previous problem (5.3), the magnitude of the momentum transferred during the hit is

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A hockey player is moving northward and suddenly turns westward with the same speed to avoid an opponent. The force that acts on the player is

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A body of mass 2kg travels according to the law x(t) = pt + qt2 + rt3

Where p = 3 m s-1, q = 4 m s-2 and r = 5 m s-3.


The force acting on the body at t = 2 seconds is