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CBSE Class 9 Answered

A bus driver decreases speed from 80km/h to 60km/h in 5 seconds find acceleration
Asked by ranjinimp | 18 Jul, 2019, 07:08: PM
answered-by-expert Expert Answer
we have the eqn.,  v = u+ a×t   ................(1)
where v is final velocity, u is initial velocity and a is acceleration
 
initial velocity = 80 km/hr = 80×(5/18) = 22.22 m/s
final velcity = 60 km/hr  = 60×(5/18) = 16.67 m/s
 
acceleration = (v-u)/t = (16.67 - 22.22 )/5 = -1.11 m/s
Answered by Thiyagarajan K | 18 Jul, 2019, 08:47: PM

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