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Class 9
Science
Force and Laws of Motion
two objects each of mass 1 5 kg are moving in th...

Question:
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 m s^-1 before the collision during which they stick together. What will be the velocity of the combined object after collision?

Answer:

Mass of first objects, m₁ = 1.5 kg

Mass of second object, m₂ = 1.5 kg

Velocity of m₁ before collision, v₁ = 2.5 m/s

Velocity of m₂, moving in opposite direction before collision, v₂ = −2.5 m/s

(Negative sign arises because mass m₂ is moving in an opposite direction)

We know that

Total momentum before collision = Total momentum after collision

m₁v₁ + m₂ v₂ = (m₁ + m₂) v

1.5(2.5) + 1.5 (−2.5) = (1.5 + 1.5) v

3.75 − 3.75 = 3 v

v = 0 / 3 = 0

Hence, the velocity of the combined object after collision is 0 m/s.

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Question:
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 m s^-1 before the collision during which they stick together. What will be the velocity of the combined object after collision?

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Question: 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 m s-1 before the collision during which they stick together. What will be the velocity of the combined object after collision?

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Question:
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 m s^-1 before the collision during which they stick together. What will be the velocity of the combined object after collision?