Question

A ball is dropped from the height 80 m,after 2second another identical ball is thrown downward.What is the initial speed of second ball such that it hits the ground simultaneously​

Answer 1

Answer:

40m/s

Explanation:

so let's first calculate for the 1st ball :-

height = 80m

time = ?

calculate it's total time taken :-

$t = \sqrt{2h \div g}$

putting values & solving we get

t = 4 sec

now consider 2ND ball ,

we will 1St calculate using 1dimension motion !

v=u+at

since ball stops we will have final velocity as 0

0=u-gt

u=gt

u=10*4

u=40

I hope u understood

good day