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A 500-kg motorcycle, going at 20 m/s, crashes into a stationary 1000-kg car. Assuming a perfectly inelastic collision, what will be the velocity of the

wreckage?

User Stefos
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1 Answer

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In a perfectly inelastic collision, the two objects stick together after the collision and move as a single combined object.

To solve the problem, we can use the law of conservation of momentum, which states that the total momentum of a system is conserved in the absence of external forces.

Before the collision, the momentum of the motorcycle is:

P1 = m1v1 = 500 kg * 20 m/s = 10000 kgm/s

where m1 is the mass of the motorcycle and v1 is its velocity.

The car is stationary, so its momentum before the collision is:

P2 = m2v2 = 1000 kg * 0 m/s = 0 kgm/s

where m2 is the mass of the car and v2 is its velocity.

The total momentum of the system before the collision is:

P1 + P2 = 10000 kg*m/s

After the collision, the combined mass of the wreckage is:

m = m1 + m2 = 500 kg + 1000 kg = 1500 kg

Let's assume that the wreckage moves at a velocity v after the collision.

By the law of conservation of momentum, the total momentum of the system after the collision is equal to the total momentum before the collision:

P = m*v

P = P1 + P2

10000 kg*m/s = 1500 kg * v

v = 10000 kg*m/s / 1500 kg = 6.67 m/s

Therefore, the velocity of the wreckage after the collision is 6.67 m/s.

User Nitin Agarwal
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