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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