A fireman 46.0 m away from a burning building directs a stream of water from a ground-level fire hose at an angle of 26.0° above the horizontal. If the speed of the stream as it leaves the hose is 40.0 m/s, at what height will the stream of water strike the building?
m (above ground level)
2007-02-27 06:28:10 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Physics
ignoring the tendency for things to fall in a parabola
s=46/cos(26) = 48.95m
Pythagoras: 48.95^2-46^2 = b^2
|b| = 16.7m
2007-02-27 07:02:05 · answer #1 · answered by SS4 7 · 0⤊ 0⤋
resolve the motion into x and y components
r=(vcos(26)t)i+(-1/2gt^2+vsin(26)t)j
the time for the horizontal component to get to 46 m is
t=46/(40cos(26))=1.28 s
the height at this time is -1/2(9.8)(1.28)^2+40sin(26)(1.28)=14.4 m
2007-02-27 15:10:23 · answer #2 · answered by Rob M 4 · 0⤊ 0⤋