Question

from top of a tower of height 280m a stone is projected vertically up with velocity 5ms per second square take g=1 per second square find time taken by stone to reach ground ​

Answer 1

Answer:

The time at which stone hits the ground can be found by s=ut+21gt2

∴300=0×t+21×9.8×t2

∴t=7.82s

Now, the time for sound to travel 300m is t=340300=0.88s

Therefore, total time will be addition of the two times. 

t=7.82+0.88=8.7s