Same chapter3 marksDifficulty: Medium
Explain why a body moving in a circle at constant speed is said to be accelerating.
Laws of Motion
3 marksDifficulty: Medium
State the law of conservation of linear momentum and derive it from Newton's third law.
Original Khojo Papers practice question — not from a past board paper.
Answer
In the absence of an external force the total linear momentum of a system stays constant. When two bodies interact, the force on the first from the second is equal and opposite to the force on the second from the first, so the rates of change of their momenta are equal and opposite and the total does not change.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
This is the principle behind recoil and rocket propulsion.
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