Answer:
0.97s
Explanation:
First of all solving the second equation of motion in the vertical direction we have
Vy= Vosinစ
= 5m x sin 30= 2.5m/s
So solving for t time in second equation of motion we will have
t= - Vy +or- √(Vy²- 4{g/2)- h)/ (2g/2)
Substituting 7m for h
We have
t = -2.5+or- √ 2.5²-4(4.9)-7/9.3
We have
t= 0.97s as the positive rational answer