A bus decreases its speed from 80 km h–1 to 60 km h–1 in 5 s. Find the acceleration of the bus.
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Solution
Given, the initial velocity (u) = 80km/hour = 80000m/3600s= 22.22 m.s-1
The final velocity (v) = 60km/hour = 60000m/3600s= 16.66 m.s-1
Time frame, t = 5 seconds.
Therefore, acceleration (a) =(v-u)/t = (16.66 m.s-1 – 22.22 m.s-1)/5s
= -1.112 m.s-2
Therefore, the total acceleration of the bus is -1.112m.s-2. It can be noted that the negative sign indicates that the velocity of the bus is decreasing.
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