Question

7A stone is dropped from the top of a tower.
When it has fallen by 5 m from the top, another
stone is dropped from a point 25 m below the
top. If both stones reach the ground at the same
moment, then height of the tower from ground
is (Take g = 10 m s2)
(a) 45m
(b) 50 m
(c) 60 m
(d) 65 m
​

Answer 1

Answer:

→ (a) 45m

Explanation:

let the height of the tower from ground be h , g = 10m/s²

for the first stone v² = 2gh , v = √2gh = 10m/s

h-5 = 10t +5t²

for the second stone

h - 25 = 5t²

t = 2 sec

h = 45 m.

→ (a) 45m