Water being hosed into the air.

• rkum99
In summary, the question involves adjusting a garden hose nozzle for a hard stream of water and then quickly moving it away from vertical. The water striking the ground next to the person for 2.0 seconds is used to find the water speed as it leaves the nozzle, which is calculated to be 9.05 m/s using the equation Δx = Vo t + 1/2 at^2. The time of 2 seconds is used because that is how long it takes for the last drop of water to hit the ground, similar to a rock being thrown into the air.

Homework Statement

Suppose you adjust your garden hose nozzle for a hard stream of water. You point the nozzle
vertically upward at a height of 1.5m above the ground. When you quickly move the nozzle away
from the vertical, you hear the water striking the ground next to you for another 2.0s. What is
the water speed as it leaves the nozzle?

Homework Equations

Δx =Vo t + 1/2 at^2

The Attempt at a Solution

Δx =Vo t + 1/2 at^2
-1.5m = (2s) Vo + (1/2) (-9.8 m/s^2) (2s)^2
-1.5m = (2s) Vo - 19.6 m
Vo = 9.05 m/s

Now the above solution seems to be correct, but I am not sure why t should = 2s.
I ended plugging 2 sec. in without really thinking about it, but now I am not able to
spatially visualize what is going on with the water.

Any help appreciated.

This is just a very standard linear kinematics question that's been verbally tarted up. The point is that once the hose is moved away from vertical the last 'drop' of water to leave the nozzle hits the ground 2s later. So you're right to use 2s as the time in this case. This problem is mathematically identical to the usual rock/ball/textbook/whatever being thrown into the air.

Hello!

Thank you, that makes sense now. :)

What is the purpose of hosing water into the air?

The purpose of hosing water into the air is typically for irrigation or to create a misting effect for cooling or humidifying purposes. It can also be used for water displays or experiments.

How does hosing water into the air affect the environment?

Hosing water into the air can have both positive and negative effects on the environment. On one hand, it can help to water plants and crops, which is beneficial for agriculture. On the other hand, it can contribute to water waste and air pollution if not used efficiently.

What factors can influence the height and trajectory of the water when hosed into the air?

The height and trajectory of water when hosed into the air can be influenced by several factors, including the pressure of the water source, the angle at which the hose is held, and wind speed and direction.

How does the temperature of the water affect its behavior when hosed into the air?

The temperature of the water can affect its behavior when hosed into the air. Warmer water tends to evaporate faster, creating a larger misting effect, while colder water may create larger droplets and a heavier spray.

Are there any safety precautions to consider when hosing water into the air?

Yes, there are a few safety precautions to consider when hosing water into the air. It is important to make sure the water source is clean and free of any chemicals or contaminants. It is also important to be mindful of any potential hazards, such as slippery surfaces or electrical equipment, and to use caution when handling the hose and nozzle.