Lesson 9 of 12 · Forces
Experiment⭐ 30 XP⚡ Spark LabPressure in Solids and Fluids
Pressure in Solids and Fluids.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Speed isn't the same as force. Don't mix them up.
Mind = Blown
⚡ Static electricity is the same physics as lightning, just smaller.
Make a hypothesis first
Guess: where does the energy go?
What You'll Learn
Pressure is force per unit area, in pascals. Spreading a force over a larger area lowers the pressure, which is why snowshoes work and a drawing pin does not. In a fluid, pressure also increases with depth as p = ρgh.
Key Words
Tap a word to see its definition.
Materials Needed
- rectangular block
- tray of damp sand
- ruler
- newton meter
Safety First
- Wash hands after handling sand and keep it out of eyes.
Steps
Read the explanation above and note the two key terms before you start.
Press a block onto damp sand on its largest face, then its smallest, using the same downward push. Measure both indentation depths and both contact areas, and relate the results to p = F/A.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2A force of 60 N acts on 0.02 m². The pressure is:
Where you see this in real life
You use this every time you flip a light switch, ride a bike, or kick a ball.
Stretch Challenge
Try this in real life this week.
Time how long a small ball rolls down something, then change the slope and try again.
For the dinner table
“Show me something at home that uses this kind of energy.”
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Pressure in Solids and Fluids
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