Question

a stone is thrown vertically upward with a speed of 20m/s.The time(in seconds) taken to return to its point of projection back is (g=10m/s)

Answer 1

Hi dear !
here is your answer !!!

time taken by to back again = 2u/g

=> 20× 2 / 10


4 sec .

hope it help you !!!!!

thanks !!!