Two objects, each of mass 1.5 kg, are moving in the same straight line but in opposite directions. The velocity of each object is 2.5 ms^{ -1 }before the collision during which they stick together. What will be the velocity of the combined object after collision?

Asked by Vishal kumar | 2 years ago | 265

Given, the mass of the

objects (m1 and m2) = 1.5 kg

Initial velocity of the first object (u1) = 2.5 m/s

Initial velocity of the second object, which is moving in the opposite direction (u2) = -2.5 m/s

When the two masses stick together, the resulting object has a mass of 3 kg (m_{1} + m_{2})

Velocity of the resulting object (v) =?

As per the law of conservation of momentum, the total momentum before the collision is equal to the total momentum after the collision.

Total momentum before the collision = m_{1}u_{1} + m_{2}u_{2}

= (1.5 kg) (2.5 m/s) + (1.5 kg) (-2.5 m/s) = 0

Therefore, total momentum after collision = (m_{1}+m_{2}) v = (3 kg) v = 0

Therefore, v = 0

This implies that the object formed after the collision has a velocity of 0 meters per second.

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