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CBSE Class 9 Answered

A stone dropped from roof of the building takes 4s to reach the ground.Calculate the height of the building? 
Asked by nisha_vini29 | 03 Nov, 2018, 01:13: PM
answered-by-expert Expert Answer
If a stone is dropped from a height h above ground, then this height is calculated using the equation " h = (1/2)gt2 ",
where t is time taken for the stone to reach ground.
 
Hence the height of the building, h = (1/2)×9.8×4×4 = 78.4 m
Answered by Thiyagarajan K | 04 Nov, 2018, 02:07: AM

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CBSE 9 - Physics
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