Question

A body is thrown vertically upward and attains maximum height in 3 seconds.What is the initial velocity?

Answer 1

$h=\frac{v_0^2}{2g}$ ;

$h=v_0t-\frac{gt^2}{2}$ ;

So, we get

$\frac{v_0^2}{2g}=v_0t-\frac{gt^2}{2} \to v_0^2-2gtv_0+g^2t^2=0$ or $v_0^2-58.86v_0+866.1249=0\to$

$v_0=29.43m/s$