Wiring a mains plug sim
Drag the brown, blue and green-and-yellow cores onto the terminals of a real three-pin plug seen from the back, tighten the screws, choose the strip length, work out I = P ÷ V and fit the right fuse, clamp the cable grip on the sheath, then run the checks, which name every fault, why it matters and what it would do, and see what earthing does when a live wire touches the metal case.
Practical electricity: the three-pin plug, the fuse and earthing · covers the O-Level, IGCSE, GCSE topic
What the sim shows
Model. A BS 1363-type plug seen from the back with its cover off. Mains 230 V a.c., 50 Hz (Singapore). Normal current I = P ÷ V; the fuse is the smallest of 3, 5, 13 A above it. Appliance powers are typical, chosen values. Terminal holes 7 mm deep with the screw 3 to 6 mm in, and three strip lengths (3, 7, 14 mm) for all three cores together (chosen; no stray strands). The cores are cut to length for their terminals. The grip counts as on the sheath when the sheath passes its top edge by 2 mm. Fuse cartridge 25.4 mm × 6.3 mm; colours 3 A red, 13 A brown, 5 A black. The fault demonstration is described in words only. Nothing is plugged in.
- The fuse in the clips (or the empty clips)
- Plug (cover off) in a holder, cover and screw, fuse box, screwdriver
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
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- Adding vectors by scale drawing simSet two forces or two velocities, pick a scale, draw them head to tail or as a parallelogram, then measure the resultant with a ruler and a protractor and compare it with the calculated value.
- Atom and nuclide builder simDrag protons, neutrons and electrons into an atom; read Z, A, the element, the nuclide notation and the charge, see whether the nucleus is stable or radioactive, and compare isotopes side by side.
- Centre of gravity of a plane lamina simHang a card from a pin at three holes, mark the plumb line each time, find the centre of gravity where the lines cross, and check it by balancing on a pencil point.
- Charging by rubbing: only electrons move simRub a polythene, acetate or glass rod with wool or silk, watch electrons move from one to the other, then bring the rod near a hanging charged rod or scraps of paper: like charges repel, unlike attract, and a charged rod pulls a neutral one.
- Circular motion: the whirling bung simWhirl a rubber bung on a string: set its speed, radius and mass and read the pull on a newton-meter, let go and watch it leave along the tangent, then hang slotted masses on the string, whirl until the paper clip holds steady, time ten turns and plot F against v².