The aim: Create a 3.3V source from a –5V supply. You can obtain a precise, positive-output voltage from a negative-voltage supply with a boost converter and a linear regulator. The input and output ...

Electrical quantities revolve around positive and negative ... Current is measured using an ammeter close ... The direction of conventional current is the direction marked on all circuit diagrams.

Learn how electric circuits work and how to measure current and potential difference with this guide for KS3 physics students aged 11-14 from BBC Bitesize.