Question

You are throwing a stone straight-up in the absence of air friction. The stone is caught at the same height from which it was thrown. the speed of the stone when thrown is equal to the speed when caught.A. TrueB. False

Answer 1

Answer:

A. True

Explanation:

When a stone is thrown straight-up, it has an initial velocity which decreases gradually as the stone move to maximum height due to constant acceleration due to gravity acting downward on the stone, at the maximum height the final velocity of the stone is zero. As the stone descends the velocity starts to increase and becomes maximum  before it hits the ground.

Height of the motion is given by;

$H = \frac{u^2}{2g}$

g is acceleration due to gravity which is constant

H is height traveled

u is the speed of throw, which determines the value of height traveled.

Therefore, when the stone is caught at the same height from which it was thrown in the absence of air resistance, the speed of the stone when thrown will be equal to the speed when caught.