Question

A rock is thrown from the edge of a cliff with a horizontal velocity component vx. The rock travels a horizontaldistance x before it strikes the ground. In order for the rock to travel a horizontal distance 2x, what must be the initial horizontal velocity of the rock in terms of vx?

Answer 1

The horizontal motion of the rock is a rectilinear motion. Then it is described as:

`v=(d)/(t)`

If we want the distance to be 2x in the same time then the velocity will have to be:

`\begin{gathered} v_x=(2x)/(t) \\ (v_x)/(2)=(x)/(t)_{} \end{gathered}`

Therefore the velocity will have to be:

`(v_x)/(2)`

and the answer is a.