Compound machines are made up of two or more simple machines working together.
They are classified into groups:
Motors produce movement. They can be electric or gas.
Gears are wheels with teeth that produce movement.
Electric circuits have switches and wires. They help electricity flow through the different parts of a machine
Electronic circuits are electric circuits with very small parts called microchips.
|Motor by Miguel Díaz from flickr|
|Gears by ralphbijker from flickr|
|Electric circuit by Leslie Wong|
|Microchip from pixabay|