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Question
A racing car, initially at rest, picks up a velocity of 180 kmh−1 in 4.5 s. Calculate
- acceleration
- distance covered by the car.
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Solution
Initial velocity of car = u = 0
Final velocity of car = v = 180 kmh−1 = `180xx5/18` ms−1
v = 50 ms−1
Time = t = 4.5 s
v = u + at
50 = 0 + a (4.5)
4.5a = 50
a = `50/4.5` = 11.11 ms−2
(Distance) S = ut + `1/2` at2
S = `0(4.5)+1/2xx50/4.5xx(4.5)^2`
S = 0 + 25 × 4.5
S = 112.5 m
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