Same chapter3 marksDifficulty: Medium
Distinguish between mass and weight.
Laws of Motion
3 marksDifficulty: Medium
What is meant by free fall, and why does a feather fall more slowly than a stone in air but at the same rate in a vacuum?
Original Khojo Papers practice question — not from a past board paper.
Answer
Free fall is motion under the action of gravity alone. In air the feather has a large surface area for its weight, so air resistance is comparable with its weight and slows it greatly, while for the stone the resistance is negligible. In a vacuum there is no air resistance, so both have the same acceleration g and fall together.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Galileo's conclusion holds only where air resistance can be ignored.
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