When a big fish swims into an oncoming smaller fish and swallows it, the momentum of the two-fish system remains the same.
The Law of conservation of momentum is important as it states that the total momentum that occurred in the initial state of the system remains the same as the momentum that exists in the final state of the system. This conservation principle helps to determine the initial and final velocity of a system that undergoes collision. This collision can be either elastic or inelastic.
So, in this case, the same principle is used as when a big fish swims into a smaller fish and also swallows it, then there will be no change in the system as the momentum of the two-fish system remains the same.
But when the momentum of the big fish exists in the same condition but since the final momentum is to be true, there arises a combined mass of the big fish as well as the small fish, whereas the case of speed must be reduced.
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