Area = displacement sim
A tacho-generator on the end pulley's shaft makes a voltage in step with the trolley's speed, and the pen's servo sets the pen 800 mm above the zero l
Area = displacement · covers the GCSE, IGCSE, O-Level topic
What the sim shows
A tacho-generator on the end pulley's shaft makes a voltage in step with the trolley's speed, and the pen's servo sets the pen 800 mm above the zero line for every 1 m/s: forward is up, reverse is down. The paper moves left at a steady 60 mm/s, so the pen draws the velocity-time graph. Its gradient is the acceleration. The area between the line and the time axis is the displacement, and the counter on the left, driven from the other pulley, shows the same number. Area below the axis counts as negative: the trolley is coming back. Below, the chart laid flat, with the area shaded.
- Pen and trace: velocity against time
- Shaded: the area under the line, the displacement (below the axis counts as negative)
- Gradient triangle: Δv ÷ Δt = acceleration
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
Need a version for your exact set-up? Have one made: US$49 a figure in an order of 5.
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