# Can you confirm a simple Physics Velocity Question?

#### pinnacleprouk

1. The problem statement, all variables and given/known data

Object a Mass 6kg moving velocity 5m/s is followed by a second object mass 8kg velocity 8m/s in the same straight line.

If the two objects are joined together after collision and move in the original direction, calculate heir common velocity.

3. The attempt at a solution

Now have either:

6x5 - 8x8 = 14V

-34 = 14V

-34/14 = V

V = -2.42m/s

or 5x6 + 8x8 = 14V

94 = 14V

94/14 = V

V = 6.71m/s

Which one is right?

#### yaser1989

The second one is right because both of the objects are moving in the same direction hence you would ADD the initial momentum of each mass.

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