Question

a body of mass 2 kg moving with a uniform velocity of 40mper s collide with another at rest .to two together begins to move with uniform velocity of 25 m per s.find the mass of other
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Answer 1

Correct question:-

A body of mass 2kg moving with a uniform velocity of 40m/s collides with another body at rest. If the two bodies together begin to move with uniform velocity of 25m/s. Find mass of the other body.

Given:-

→Mass of the 1st body(m₁)=2kg

→Initial velocity of the 1st body(u₁)=40m/s

→Initial velocity of the 2nd body(u₂)=0

(as the 2nd body was at rest)

→Velocity of the combined body after

collision=25m/s

To find:-

→Mass of the 2nd body(m₂)

Solution:-

By using Law of Conservation of momentum,we get:-

=>m₁u₁+m₂u₂ = (m₁+m₂)v

=>2(40)+m₂(0) = (2+m₂)25

=>80 = 50+25m₂

=>25m₂ = 80-50

=>25m₂ = 30

=>m₂ = 30/25

=>m₂ = 1.2kg

Thus,mass of the other body is 1.2kg.