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CBSE Class 9 Answered

A particle is projected upward with speed 105 m/s done the time after which it is hit the ground is: 1.20 s 2.21 s 3.22 s 4.25 s
Asked by santoshkumargupta644 | 25 Jan, 2021, 09:01: AM
answered-by-expert Expert Answer
Time t to reach highest point , t = ( u / g )
 
where u is initial projection speed and g is acceleration due to gravity.
 
t = 105 / 9.8 = 10.71 s
 
Time taken from highest point to ground also 10.71 s
 
Hence, Time to reach ground = 2 × 10.71 = 20.42 s ≈ 20s
Answered by Thiyagarajan K | 25 Jan, 2021, 12:19: PM

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