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4 years ago

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a 2kg marble is moving at 3 m/s when it strikes another 4kg marble moving in the opposite direction at -3 m/s. What will be the

velocity of the 4kg marble after the collision of the 2kg marble's new velocity is -4 m/s. Also state the direction of the 2kg marble after they hit.

1 answer:

Elan Coil [88]4 years ago

4 0

Momentum is conserved after the collision

Momentum of 2 Kg before collision = 2 * 3 = 6
Momentum of 4 kg before collision = 4 * -3 = -12

so 6 + -12 = 2 * -4 + 4 *x where x is velocity of 4kg marble.

4x - 8 = -6
4x = 2
x = 0.5

Velocity of 4 kg marble is 0.5 m/s after collision

The 2 kg marble will move in the opposite direction to which it was moving before the collision.

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= 90 x 9.8

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