6.2k views
2 votes
A fireman, 25.7 m away from a burning building, directs a stream of water from a ground level fire hose at an angle of 47.5° above the horizontal. if the speed is 38.4 m/s, at what height will the stream of water hit the building?

User Hu Qiang
by
7.5k points

1 Answer

3 votes
The coordinates of a particle of water "t" seconds after it leaves the end of the fire hose will be
.. (x, y) = (38.4*cos(47.5°)t, -4.9t^2 +38.4*sin(47.5°)t)

Solving for t, we have
.. t = x/(38.4*cos(47.5°)

For x = 25.7 meters, t is about 0.99065 seconds.
Then y will be
.. -4.9*(0.99065)^2 +38.4*sin(47.5°)*0.99065 = 23.238 . . . . meters

The water will hit the building about 23.24 meters above the height of the hose.
User PW Kad
by
7.4k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories