Question

A 2kg object travels to the right at 5.5 m/s after colliding with a 3kg object, initially at rest, what are the speeds of each object after the collision l?

Answer 1

Answer:

Velocity of Object with 2 kg= 3.390 m/s

Velocity of Object with 3 kg= 3.404 m/s

Explanation:

From the picture, it can be seen that object B is initially at rest while object A is travelling at a speed of 5m/s. After the collision, Object A moves at an angle of 65 degrees while object B moves at an angle of 37 degrees.

We also know that momentum of a closed system is conserved.

Initial momentum along the x-axis = 2*5.5 = 11

Initial momentum along y-axis = 0

Final momentum along x-axis= a*Cos(65)*2 +b*Cos(37) *3= 11 (a is the velocity of object A of 2 kg after collision where as b is the velocity of object B of 3 kg after collision. velocity is multiplied by cosines of the angle from x axis to give the horizontal component of the velocities).

Final momentum along y-axis = a*Sin(65)*2 - b*Sin(37)*3 =0 (We can see that vertical components of velocity are opposite in direction to each other)

Solve both the equations simultaneously for a and b.