In episode 4 of the series, we look at how electrical equipment is designed to use the right amount of current for the voltage supply that it’s designed for. After a brief recap on electric current (that we examined in Episode 3) we look at what voltage is and how it is measured. We then look at the concept of resistance. At a simple level, some materials are conductors and some materials are insulators, but not all conductors conduct equally well. The amount of current that flows in a household appliance depends on the appliance’s resistance!

Originally released by Liacos Educational Media, 2020. Streaming video file encoded with permission for digital streaming by Infobase on June 22, 2021. Teacher's guide available under Additional info tag.