Quick challenge · about 10 minutes

Ten questions, mixed from the whole course

Five calculations with fresh numbers every time, plus five concept questions drawn at random. Hints are there if you need them. At the end you get a score and a review of anything you missed.

Spaced review

Questions you get wrong anywhere on the site come back here after 1, 3, 7, 14 and 30 days. Each correct answer pushes a question further out; a wrong one starts it again. Reviewing at growing intervals helps you remember for longer.

More practice

Quick timed rounds in the speed drills (colour codes, prefixes, Ohm’s law), or printable worksheets with answer keys for pencil-and-paper practice.

For calculation questions, type a number in the unit shown. Answers within 2% count as correct, so rounding is fine. You can type prefixes too, for example 0.22k.