Question

A 8 kg ball is moving at a speed of 12 m/s. It collides with 2 balls simultaneously, each having a mass of 3 kg. What is the final velocity of EACH BALL? (Draw a picture to help you answer the question)

Answer 1

6m/s

Answer 2

To solve this problem, let's make a diagram to visualize the situation:

------- ------- -------
| | | | | |
| 8kg | | 3kg | | 3kg |
| | | | | |
------- ------- -------

The 8 kg ball collides with the two 3 kg balls simultaneously. In an ideal situation with no energy loss, the total momentum before the collision should be equal to the total momentum after the collision.

Let's assume the final velocity of each ball after the collision.

The momentum p is given by the equation p = m * v, where p is momentum, m is mass, and v is velocity.

Therefore, the momentum before the collision is:
(8 kg) * (12 m/s) + (3 kg) * (0 m/s) + (3 kg) * (0 m/s) = 96 kg*m/s

After the collision, the momentum of the 8 kg ball becomes (8 kg) * vf8, and the momentum of each 3 kg ball becomes (3 kg) * vf3.

So, the momentum equation after the collision is:
(8 kg) * vf8 + (3 kg) * vf3 + (3 kg) * vf3 = 96 kg*m/s

Simplifying the equation, we get:
8 vf8 + 6 vf3 = 96

Since each ball is colliding at the same time and the initial velocity of each 3 kg ball is 0 m/s, we can assume that they split the total momentum equally.

So, vf3 = vf3 (final velocity of each 3 kg ball) and vf8 = vf8 (final velocity of the 8 kg ball).

Substituting these values into the equation, we get:
8 vf8 + 6 vf3 + 6 vf3 = 96
8 vf8 + 12 vf3 = 96

To solve for vf3 and vf8, we have two equations with two variables:

8 vf8 + 12 vf3 = 96
vf8 = (96 - 12 vf3) / 8

Substituting the second equation into the first equation, we get:
8 (96 - 12 vf3) / 8 + 12 vf3 = 96
96 - 12 vf3 + 12 vf3 = 96
96 = 96

This equation is true, which means any value of vf3 and vf8 that satisfy this equation is a valid solution.

Therefore, we cannot determine the specific values for vf3 and vf8. All we know is that their sum should be equal to 12 m/s.

So, the possible final velocities for each ball could be vf3 = 4 m/s and vf8 = 8 m/s, or vf3 = 6 m/s and vf8 = 6 m/s, or any other combination as long as vf3 + vf8 = 12 m/s.