A U-turn: distance and displacement sim
The odometer on the trolley turns with its wheel whichever way it rolls, so it adds up every move: the distance, a scalar.
A U-turn: distance and displacement · covers the GCSE, IGCSE, O-Level topic
What the sim shows
The odometer on the trolley turns with its wheel whichever way it rolls, so it adds up every move: the distance, a scalar. The dial at the end of the track is turned by the cord loop, so its needle shows only where the trolley is now: the displacement from O, a vector, plus to the right and minus to the left. Out 0.40 m and back 0.60 m: the odometer reads 1.00 m, but the dial reads −0.20 m.
- Odometer on the trolley: the distance
- Dial: the displacement from O
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.
More physics sims
- Energy resources: power a town simDrag the faders on a model town's control desk to switch on coal, gas, nuclear, biofuel, geothermal, hydroelectric, wind, solar and tidal power, change the wind, the sky and the hour, and see hour by hour whether the supply meets the town's demand, with scores for hours met, CO₂, renewables and rough cost; save your mixes to a table and sort the resources by renewable, from the Sun and available at any hour.
- Evaporation and boiling simWeigh a dish of water or ethanol on a balance as it evaporates, changing the temperature, the surface area and a desk fan's air speed; watch a wet-bulb thermometer cool below a dry one; then heat water on a hotplate until bubbles form all through it and the temperature stays at the boiling point.
- Floating, sinking and upthrust simLower a cylinder on a newton-meter into water, salt water or cooking oil from a displacement can that spills into a beaker on a balance: watch the reading fall as the upthrust grows, find U = weight in air − reading in the liquid, predict float or sink from the densities, and see a wooden block float deeper in oil and higher in salt water; cards show a hydrometer and a steel boat.
- Magnetic field of bar magnets simPlot the field round a bar magnet the classic way, moving a plotting compass and marking a pencil dot at each end of its needle, then sprinkle iron filings, put two magnets N–N (finding the neutral point X) and N–S, and add the Earth's field to see where it cancels the magnet's.
- Magnetic field of a wire and a solenoid simPass a current up a wire through a card ringed with plotting compasses and iron filings, reverse it and raise it with a rheostat, then thread a coil through the card and see its field look like a bar magnet's, with its N end found by the right-hand grip rule and made stronger by more current, more turns and an iron core.
- Potential divider and potentiometer simDrag the sliding contact of a real slide rheostat used as a potentiometer (or choose R1 and R2 on a two-resistor board), measure V_in and V_out with a digital voltmeter, record V_out against the contact's position in an empty table, see your own points make a straight best-fit line through the origin, and check V_out = V_in × R2 ÷ (R1 + R2) against your readings; a load across the output (beyond the syllabus) bends the line.