Prove that if a body is thrown vertically upward, the time of ascent is equal to the time of descent.
Prove that if a body is thrown vertically upward, the time of ascent is equal to the time of descent.
For upward motion
$v=u-g t$ or $0=u-g t_{1}$
or $t_{1}=\frac{u}{g}$ $....(1)$
For downward motion
$v=u+g t_{2}$ or $v=0+g t_{2}$
As the body falls back to the earth with the same velocity, it was thrown vertically upwards.
$\therefore \quad v=u$
$u=0+g t_{2}$ or $t_{2}=\frac{u}{g}$ $...(2)$
From $(1)+(2)$ the statement is proved.
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