A stone is dropped from the edge of a roof How long does it take to fall 4 - Science - Gravitation

Question

A stone is dropped from the edge of a roof How long does it take to
fall 4 9 m? (b) How fast does it move at the end of that fall? (c
What will be its acceleration after 1 second and after 2 seconds?

Bakul Biswas · Accepted Answer

Dear Student, Here u=0,h=4 9m,g=-9 8 $m / s^{2}$ (it is taken as negative) we have the relation $v^{2} = u^{2} + 2 g h p u t t i n g t h e v a l u e s v^{2} = 0 + 2 \times (- 9 8) \times 4 9 v = - 9 8 m / s (\min u s s i g n s h o w s t h a t i t i s i n t h e d o w n w a r d d i r e c t i o n) n o w f o r c a l c u l a t i n g t i m e w e h a v e v = u + g t p u t t i n g t h e v a l u e s - 9 8 = 0 + (- 9 8) t t = 1 \sec (w e c a n a l s o c a l c u l a t e t i m e b y u \sin g h = u t + \frac{1}{2} g t^{2}) a c c e l e r a t i o n a f t e r 1 \sec a n d 2 \sec w i l l r e m a i n s a m e (9 8 m / s^{2}) f o r a f r e e l y f a l l i n g b o d y$ Hence answers a)1 sec b)9 8m/s(with negative sign) c)9 8 $m / s^{2}$ Hope this information will clear your doubts about the topic If you have any more doubts just ask here on the forum and our experts will try to help you out as soon as possible Regards

A stone is dropped from the edge of a roof. How long does it take to fall 4. 9 m? (b) How fast does it move at the end of that fall? (c What will be its acceleration after 1 second and after 2 seconds?