Firefighters are throwing a jet of water at a burning building,
using a high pressure hose that gives the water a speed of 25.0
m/s when exiting the nozzle. Once it leaves the hose, the water moves with
projectile motion. Firefighters adjust the elevation angle of the
hose until it takes 3.00 s for the water to reach a building 45.0 m away
away. Ignore air resistance and assume that the hose nozzle
It is at ground level.
1) Investigate and explain the following concepts: vector, scalar, velocity,
speed, distance, displacement and reference system.
2) Solve the following numerically, completely and in detail:
a) Calculate the angle of elevation.
b) Determine the speed and acceleration of the water at the highest point of its
trajectory.
c) Determine the height above the ground at which the water hits the building.
and with what speed value it does it.
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3) Analyze and explain how it would affect the previous results if the angle of
inclination is increased.
4) Analyze and explain how it would affect the previous results if the angle of
inclination is decreased.
5) Analyze and explain how it would affect the previous results if the magnitude
of the exit velocity through the nozzle will increase.
6) Analyze and explain how it would affect the previous results if the magnitude
of the exit velocity through the nozzle will decrease.
7) Analyze and explain how it would affect the previous results if the wind were
a variable to consider.
8) If the water jet reached its maximum height before colliding with the
wall of the building, what value should the magnitude of the acceleration have?
horizontal and vertical at that moment.
9) If the water jet reached its maximum height before colliding with the
wall of the building, what value should the horizontal and vertical speed have in
that moment.
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