A stone is allowed to fall freely from a certain Height. Neglecting air resistance, which graph represents the variation of velocity `v` with time `t` ?

Options

A.
B.
C.
D.

Answer

C

Explanation

During the fall, `v=0+gt` i.e. `v=gt`
Which is of the form `y=mx`
a straight line passing through the origin The velocity is negative, as it is directed downwards. Next, when the stone rebounds, with a velocity `v^(`)`
Then `v=v^(`)`-gt`
or `v=-gt+v^(`)`
which is again a straight line with negative slope.