• # question_answer A body is projected vertically upwards. If ${{t}_{1}}$ and ${{t}_{2}}$ be the instants at which it is at a height h above the point of projection, while ascending and descending respectively, then A)  $h=g{{t}_{1}}{{t}_{2}}$              B) $h=2g{{t}_{1}}{{t}_{2}}$ C)  $h=\frac{1}{2}\,g{{t}_{1}}{{t}_{2}}$                 D)  $h=\frac{1}{4}g{{t}_{1}}{{t}_{2}}$

Taking downward direction as positive, we get $\therefore$                ?(i) $f$                   ?(ii)             From Eqs. (i) and (ii), we get $|M|=\alpha$ ${{M}^{-1}}adjM)=kI$                              ?(iii) Substituting value of u from Eq. (iii) in Eq. (i), we get $\Rightarrow$