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A gun is monted on a railroad car. The m...

A gun is monted on a railroad car. The mass of the car, the gun, the shells and the operator is 50m where m is the mass of one shell. If the velocity of het shell with respect to the gun (in its state before firing) is 200 m/s, what is the recoil speed of the car after the second shot? Neglect friction.

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A gun is mounted on a railroad car. The mass of the car, the gun, the shells and the operator is 50 m where m is th mass of one shell. The muzzle velocity of the shells is 200 m/s.
`:. Initial V_(cm)=0`
`0=49xxV+mxx200`
`rarr V=-200/49` m/s
`200/49 m/s` towards left.
When another shell is fired, then the velocity of the car with respect to the platform is
`rarr V=200/49` m/s towards let ltbRgt When another shell is fired, then teh velocity of the car with respect to the platform is,
`:.` Velocity o the car w.r.t the earth is
`=200(1/49+1/48)m/s`
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