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(a) State the law of conservation of mom...

(a) State the law of conservation of momentum. Write the expression for it. (b) Explain giving reason why does cricketer moves his hands backwards after catching a ball? (c) A body of mass 30 kg has a momentum 150 km m`s^(-1)` What is its velocity?

Text Solution

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Expression: `m_(A)u_(A)+m_(B)u_(B)=m_(A)v_(A)+m_(B)v_(B)`
Momentum =mv
`therefore 150=30xxv thereforev=(150)/(30) therefore v=5 ms^(-1)`
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