PhET Forces and MotionLinks to an external site.
Note: This week you will need a stopwatch. This can be either your phone, a physical stopwatch, or an online one. If you need an online one, simply Google “stopwatch” as Google has one built in to its site.
Select the tab labelled “Motion.”
Play around with the simulation to get familiar with it.
Investigate and click around making sure you try everything out.
Reset via the yellow reset button on the right side of the screen.
Turn on “Speed.”
At the same time, start your stopwatch and press the 50N button once.
Stop your stopwatch when the speedometer maxes out.
Question 1: Describe the motion of the crate on the skateboard.
Question 2: How long did it take to reach maximum speed?

Reset, and turn “Speed” back on.
At the same time, start your stopwatch and press the 50N button twice.

Stop your stopwatch when the speedometer maxes out. 

Question 3: Compare the observed motion to your answer in Question 1: what changed? Why?

Question 4: How long did it take to reach maximum speed?
Reset, and turn “Speed” back on.
Stack any other item on top of the crate.

Question 5: What item did you pick? Why?

At the same time, start your stopwatch and press the 50N button once.

Stop your stopwatch when the speedometer maxes out.

Question 6: Compare the observed motion to your answer in Question 1: what changed? Why?

Question 7: How long did it take to reach maximum speed?

Question 8: By comparing your answers between questions 1, 3, and 6, are there any rules that you can suggest for the relationship between mass, force, and acceleration?

Question 9: Which of Newton’s laws did we investigate via this experiment?