Classroom mode
Run it in class
Is it harder to START a box sliding or to KEEP it sliding?
Show of hands — before you project anything
Predict first: if friction were one fixed amount, would a box ever lurch when it breaks free? Then run the experiment and check.
- A Way more than you'd guess
- B About what you'd guess
- C Way less than you'd guess
Count the votes out loud. Hold them to it — then watch.
Project it (fullscreen)
Discussion prompts
- Predict first: if friction were one fixed amount, would a box ever lurch when it breaks free? Then run the experiment and check.
- Predict whether a lighter object is also harder to start than to keep sliding, then explain why using static versus kinetic grip.
- Where does the leftover force come from that jerks the box forward the instant it breaks loose?
Where it shows up in real life
- Heaving a heavy chair or laundry basket across the floor — it sticks, pops loose, then glides
- A sled on snow: hard to start, easy to keep going
- A squeaky door hinge or a violin string, which grip and slip over and over
A prediction-first worksheet — no answer key.
zero prep · no login · any projector
Winding down at home? Family mode ·
Explore every question
Is it harder to START a box sliding or to KEEP it sliding?
Predict — what do you think will happen, and why?
Talk about it
- Predict first: if friction were one fixed amount, would a box ever lurch when it breaks free? Then run the experiment and check.
- Predict whether a lighter object is also harder to start than to keep sliding, then explain why using static versus kinetic grip.
- Where does the leftover force come from that jerks the box forward the instant it breaks loose?