Question

(Ans 36.4 km)
A balloon is ascending at the rate of 14 ms at a
height of 98 m above the ground when the food
packet is dropped from the balloon. After how
much time and with what velocity does it reach the
ground ? Take g -9.8 ms 2
(Ans. 6.12s, 45.98 ms)​

Answer 1

Explanation:

taking the upward direction as +ve

u=+14 m/s

g=-9.8m/s²

h=-98

so, we the equation

s=ut+1/2at²

-98=14t-1/2*9.8*t²

4.9t²-14t-98=0

t=-(-14)±√(14²-4*4.9*-98)/(2*4.9)

t=14±46/9.8

t=60/9.8 as t≠-34/9.8

t=6.12 s

we know

v²=u²+2aS

v²=(+14)²+2*-9.8*-98

v²=2116.8

v≈46.00 m/s