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CBSE Class 9 Answered

An athelete always run for some distance before a jump. why?
Asked by kishor.kp14 | 25 Jul, 2019, 03:50: PM
answered-by-expert Expert Answer
while running athlete develops momentum in horizontal direction.
After running some distance, he jumps by applying force to ground vertically.
Then he gets normal reaction force from ground and gains momentum in vertical direction above the ground.
 
Hence due to running he has already momentum in horizontal direction, then he gains additional momentum
in vertical direction due to normal reaction force from ground.
 
These two momentum gives a resultant momentum in a direction that makes some angle to the horizontal direction.
This resultant momentum  makes athelete to jump over vertical height and also to move fast in horizontal direction
Answered by Thiyagarajan K | 25 Jul, 2019, 04:36: PM

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CBSE 9 - Physics
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