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Question
A body, initially at rest, starts moving with a constant acceleration 2 m s-2. Calculate: (i) the velocity acquired and (ii) the distance travelled in 5 s.
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Solution
Initial velocity u = 0 m/s
Acceleration a = 2 m/s2
Time t = 5 s
(i) Let 'v' be the final velocity.
Then, (v - u)/5 = 2
v = 10 m/s-1
(ii) Let 's' be the distance travelled.
Using the third equation of motion,
v2 - u2 = 2as
We get,
(10) 2 - (0) 2 = 2(2) (s)
Thus, s = (100/4) m = 25 m
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