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Question
The speed of a car increases from 10 km/h to 64 km/h in 10 seconds. What will be its acceleration?
Solution
Initial velocity u = 10 km/hr. = (10 X 1000)/3600 = 8.33 ms-1.
Final velocity = 64 km/hr = (64 X 1000)/3600 = 17.77 ms-1.
Time = 10 s.
Acceleration = (v-u)/t = (17.77- 8.33)/10 = 9.44/10 = 0.94 ms-2.
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