A fireman,50.0 m away from a burning building,directs a stream of water from a fire hose at an angle of 30.0 $\degree$above the horizontal.If the initial speed of the stream is 40.0 m/s,at what height will the stream of water strike the building?
A)9.60 m
B)13.4 m
C)18.7 m
D)22.4 m

Question

Quizplus · Accepted Answer

Using the kinematic equations,
h = vt sin θ - (1/2)gt^2
where h is the height the stream strikes the building, v is the initial speed, θ is the angle above horizontal, g is the acceleration due to gravity, and t is the time it takes for the stream to reach the building.
First, we need to find the time it takes for the stream to reach the building:
x = vt cos θ
50.0 m = (40.0 m/s) cos 30.0° * t
t = 1.443 s
Now, we can use the kinematic equation to solve for the height:
h = (40.0 m/s) sin 30.0° * 1.443 s - (1/2)(9.81 m/s^2)(1.443 s)^2
h = 18.7 m
Therefore, the stream of water will strike the building at a height of 18.7 m, which is option C.

A Fireman,50 °\degree° Above the Horizontal

A Fireman,50 $\degree$ Above the Horizontal