Got to the simulation, and select the acceleration simulation (all the way to the right). Play around with it a few minutes to get a feel for how it works.
- Determine the problem: Consider the relationship between an unbalanced force, mass, acceleration, and velocity (speed).
- Before making a hypothesis, let me tell you what you'll do!
- In the yellow box to the upper right, click on forces, masses, speed, and acceleration to display these properties. You'll do five runs.
- First run (no friction):Slide the friction bar all the way to the left, so that there is no friction. Record the mass and increase the force with the right arrow to 100 N. Record how the speed and acceleration change as the object moves for a few seconds.
- Second run (no friction):
Repeat the first run, but add the refrigerator to the top of the crate by dragging it there. Compare the results to the first run. (Don't forget to record the mass!)
- Third run (friction):
Remove the refrigerator, and slide the friction bar to medium. Record the mass, and increase the force to 100 N. Record what you observe. Now, increase the force until the crate begins to move, and record what you observe. Compare the results to the first run. Why do they differ?
- Fourth run (friction):
Keeping the friction bar at medium, add the refrigerator, and repeat the steps for the third run. Compare the results to the third run. Why do they differ?
- Fifth run:
Now, you choose a combination that you're interested in, and record the results. Are they what you expected based on your previous observations?
- Make a hypothesis: Make a prediction in regards to how the acceleration and speed will vary (or not) for the first run. Then, predict how the first run and second run will compare. Make at least one more prediction -- predict how the first run and third runwill compare.
- Test your hypotheses. (You may want to make a table for your data.)
- Analyze your data: Use the table to analyze your data.
- Draw a conclusion: How do force, mass, and acceleration relate to one another? How do speed and acceleration relate to each other? What is the effect of introducing friction?