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Question
Multiple choice Question. Select the correct option.
The speed of a car reduces from 15 m/s to 5 m/s over a displacement of 10 m. The uniform acceleration of the car is :
Options
−10 m/s2
+10 m/s2
2 m/s2
0.5 m/s2
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Solution
−10 m/s2
Explanation:
Initial velocity = u = 15 m/s
Final velocity = v = 5 m/s
Displacement = S = 10 m
Acceleration = a = ?
v2 – u2 = 2aS ;
(5)2 – (15)2 = 2a (10)
25 – 225 = 20a
a = −220/20 = -10 ms−2
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