Question

A car has 400 kgm/s worth of momentum and runs into a truck initially at rest. After the collision, the truck has 500 kgm/s worth of momentum. What must be the final momentum of the car and truck combined?

A. 400 kgm/s
B. -100 kgm/s
C. 500 kgm/s
D. 100 kgm/s

Answer 1

Option A

Step-by-step explanation:

By law if conservation of momentum we know that the the initial and final momentum of a system remains conserved . Therefore the final momentum of system will be 400 kg -m/s

Proof :-

Let the final momentum of car be " x " .

By Law of conservation of momentum ,

→ m1 u1 + m2 u2 = m1 v1 + m2 v2

→ 400 kg m/s + 0 = 500 kg - m/s + x

→ x = 400 - 500 kg m/s

→ x = -100 kg - m/s

Combined momentum = -100 + 500 = 400 kg-m/s

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