Physics-
General
Easy
Question
A point starts moving in a straight line with a certain acceleration. At a time 
after beginning of motion the acceleration suddenly becomes retardation of the same value. The time in which the point returns to the initial point is
- Cannot be predicted unless acceleration is given
The correct answer is:
In this problem point starts moving with uniform acceleration 
and after time (Position 
) the direction of acceleration get reversed i.e. the retardation of same value works on the point. Due to this velocity of points goes on decreasing and at position 
its velocity becomes zero. Now the direction of motion of point reversed and it moves from 
to 
under the effect of acceleration .
We have to calculate the total time in this motion.
Starting velocity at position is equal to zero.
Velocity at position 
[
]
Distance between and 
As same amount of retardation works on a point and it comes to rest therefore
and time required to cover this distance is also equal to 
Now for the return journey from 
Hence total time in which point returns to initial point
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