Instructions
Use this worksheet to explore the physics of pressure washing an outdoor dirty wall. Answer the questions and complete the activities to learn about pressure, force, and energy transfer. Use the space provided to write your answers.
Understanding Pressure
1. What is pressure? Write a simple definition:
2. Use the formula Pressure = Force / Area to explain how pressure washers work:
3. Why does the water come out of the nozzle in a narrow stream? What happens to the pressure when the water is focused into a smaller area?
How Pressure Washing Cleans
4. What happens to the dirt on the wall when a high-pressure stream of water hits it? Describe the physics involved:5. Draw a simple diagram of a pressure washer nozzle. Label the inlet (where water comes in) and the outlet (where water exits). Show how the water is sped up as it passes through the nozzle.
Pressure in Action
6. Why is it important to wear safety goggles when using a pressure washer? What might happen if you don’t?7. If you double the force of the water (e.g., by turning up the pressure), what effect does it have on the cleaning power? Why?
8. What are some other uses of pressure washing besides cleaning dirty walls? How does the physics of pressure apply in those situations?
Energy Transfer
9. Where does the energy come from to create the high pressure in a pressure washer? Explain the energy transfer process:10. Why do you think pressure washing is more effective than just spraying water from a garden hose? Use physics concepts to explain your answer.