Question

Q15- A body is projected vertically upwards from A, the top of
it t; sec If it is projected vertically downwards from A with the same velocity it reaches the
ground in tz second. If it falls freely, from A, Prove that it would reach the ground in time t1 t2​

Answer 1

~$\small \blue {\sf{Answer }}$✨❤

$</p><p></p><p></p><p></p><p>−h=ut1−21gt12 \\ ⇒t1h=−u+21gt1..........(i) \\ </p><p></p><p></p><p></p><p>−h=−ut2−21gt22 \\ </p><p>⇒t2h=u+21gt2.........(ii) \\ \\ </p><p></p><p>−h=−21gt32 \\ </p><p>⇒h=21gt32.........(iii) \\ \\ </p><p></p><p>From \: (i) and (ii): \\ </p><p>h[t11+t21]=21g(t1+t2)........(iv) \\ \\ </p><p></p><p>∴ By eq. (iii) and (iv) \\ </p><p>21gt32=21gt1t2 \\ \\ </p><p></p><p></p><p>⇒t3=t1t2.</p><p></p><p>$

$\huge \orange {\mathfrak{Thank You }}$