contestada

A disgruntled physics student, frustrated with
finals, releases his tensions by bombarding the
adjacent building, 13.5 m away, with water
balloons. He fires one at 38β—¦
from the horizontal with an initial speed of 23.6 m/s.
The acceleration of gravity is 9.8 m/s
2
.
For how long is the balloon in the air?

Respuesta :

Answer:

Explanation:

The balloon would require a time of

t = d/v = 13.5/ (23.6cos38) = 0.7259...s

to travel the horizontal distance.

the vertical position relative to the throw point at that time is

h = 0 + (23.6sin38)(0.7259) + Β½(-9.8)(0.7259Β²)

h = 7.9652...

so as long as the adjacent building is at least 8.0 m higher than the student position, the balloon is in the air for 0.726 s.

If the building is shorter than 8.0 m above the student, the balloon will land on the building roof and will be in the air for a longer period of time