Question

Two water balloons of mass 0.75 kg collide and bounce off of each other without breaking. Before the collision, one water balloon moved at a velocity of 3.5 m/s east, while the other moved at a velocity of 2.75 m/s west. After the collision, one balloon moves at a velocity of 1.5 m/s west. What is the velocity of the other water balloon?

Answer 1

By the law of momentum conservation:-
=>m¹u¹ + m²u² = m1v1 + m²v² {let East is +ve}
=>u¹ + u² = v¹ + v² {as m1=m2}
=>3.5 - 2.75 = v1-1.5
=>v¹ = 2.25 m/s (East)