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CBSE Class 9 Answered

A bus decreases it's speed 80 km/h to 60km/h in 5 second find the acceleration?
Asked by ChinuSwami098 | 22 Dec, 2018, 08:02: AM
answered-by-expert Expert Answer
Acceleration = rate of change of speed = change of speed / time 
 
80 kmph = 80×(5/18) = 400/18 = 22.22 m/s
60 kmph = 60×(5/18) = 300/18 = 16.67 m/s
 
acceleration = (16.67-22.22) /5  = -1.11 m/s2
Answered by Thiyagarajan K | 22 Dec, 2018, 12:13: PM

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