A moving object does not need a force to keep moving. It needs one to change its motion.
Push:
Surface under test
—
choose a surface to test
What you observed
—speed m/s
—distance m
?resultant N
Results
The resultant force
Choose what the resultant force was, and what it did.
How far the trolley ran before it stopped
Timer
0.0
Ready — place the trolley to begin
Accessibility — Adapt
Theme
Dark navy theme
Colour overlay (Irlen)
Off
Display
Reading ruler
Wider spacing (dyslexia)
Text size
100%
High contrast
Classroom / projector mode
Shape-coded lane labelsAdds a symbol to each lane label as well as its colour, so the four surfaces can be told apart without relying on colour.
Forces
Show the vertical forcesDraws weight and the normal contact force as a balanced pair. Turn off to leave only the horizontal forces on screen.
Always ask the resultant force questionNormally the question is offered as a choice after each run. Turn this on to put it in front of every pupil before the result is recorded.
Procedure
No dragging — buttons onlyEvery drag becomes one button press. Perfect technique assumed.
Sound
Launch clickA short click when the trolley is released. Turn off for a silent classroom or if sudden sounds are distracting.