Question
Thu March 12, 2015 By: Deebu Raghv

The displacement time graph of a vertically upward projected body appears as a parabola. 
 
Why is this so?
[onse the object reaches maximum height doesn't it come down with an acceleration?
 If that was so, shouldn't half of the graph be like a decelerating curve (till it reach max height) and the remaining half be an accelerating curve? (because the object is coming down under the influence of gravity with increaseing acceleration)
 
Please explain. 

Expert Reply
Priyanka Kumbhar
Fri March 13, 2015
 
When a body is movig with zero acceleration position-time graph is straight line.
When a body projected vertically upward it moves with uniform acceleration. In the given graph, at tm body reaches to maximum height and from that point body comes down, it is accelerated downwards under the influence of a qravity pull. So the motion is unifromly accelerated. Hence, the displacement time graph of a vertically upward projected body appears as a parabola. 
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