Answer:
7.74 seconds
Explanation:
u = 25 m/s
h = - 100 m
Let it takes time t to hit the ground.
Use second equation of motion
[tex]h = ut-\frac{1}{2}gt^{2}[/tex]
[tex]-100 = 25t-4.9t^{2}[/tex]
[tex]4.9t^{2}-25t-100=0[/tex]
[tex]t=\frac{25\pm \sqrt{625+4\times 4.9\times 100}}{2\times4.9}[/tex]
[tex]t=\frac{25\pm 50.84}{9.8}[/tex]
Take positive sign as time can never be negative.
t = 7.74 s
Thus, the package takes 7.74 seconds to reach the ground.
