Same chapter3 marksDifficulty: Medium
State the work-energy theorem.
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A body of mass 2 kg falls freely from rest through 20 m. Find its kinetic energy on reaching the ground and its momentum. Take g = 10 m s−2.
Original Khojo Papers practice question — not from a past board paper.
Answer
Kinetic energy 400 J and momentum 40 kg m s−1
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The kinetic energy equals the loss of potential energy, mgh = 400 J. Then v = √(2 × 400 ÷ 2) = 20 m s−1 and p = mv = 40 kg m s−1.
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