Question

A balloon is moving upward with velocity 10 m/s. It releases a stone which comes down to the ground in 5 sec. The height of the balloon from the ground at the moment when the stone was dropped is Ⓐ 40 m Ⓑ 49 m Ⓒ 75 m Ⓓ 100 m

Answer 1

Answer:

122.5 m

Explanation:

u=10m/s

t=5sec

from relation we have to find final velocity of stone

v=u+at

v=0+9.8*5..(here vertical velocity of stone os zero)

v=49m/s........... (final velocity of stone)

from relation:

v²-u²=2as

49²-0²=2*9.8*s

2401=19.6*s

s=2401/19.6

s=122.5m