Two asteroids strike head-on: before the collision, asteroid A (mA = 8.4×10^12 kg ) has velocity 3.3 km/s and asteroid B (mB = 1.31×10^13 kg ) has velocity 1.4 km/s in the opposite direction.
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Asteriod A has a mass of
.
Asteriod A moves with a velocity of
.
Asteriod B has a mass of
.
Asteriod B moves with a velocity of
.
Momentum before collision
.

Momentum before collision is
.
After head-on collision, the two asteriods stick together then mass of the asteriod is
.
Momentum after collision
.

Momentum after collision is
.
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Conservation of momentum:
\In a collision, the momentum before collision is equal to momentum after collision. \ \
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Magnitude of the velocity of the new asteroid after the collision is 0.44 km/sec.