A stone is released from the top of a tower of height $19.6\ m$. Calculate its final velocity just before touching the ground.
Given:
Initial velocity, $u=0$
Height of the tower$=19.6\ m$
$g=9.8\ m/s^2$
To do:
To find the final velocity just before touching the ground.
Solution:
On using the third equation of motion
$v^2=u^2+2gh$
Or $v^2=0+2\times 9.8\times 19.6$
Or $v^2=384.16$
Or $v=\sqrt{(384.16)}$
Or $v=19.6\ m/s$
Therefore, the final velocity of the stone just before touching the ground is $19.6\ m/s$.
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