Video and lesson investigations on the topic of gears. Key concepts include:
- Cogwheels (gearwheels) can change the direction and speed of movement.
- If a small cogwheel is connected to a large cogwheel, the small cogwheel revolves more often than the large one.
- The greater the difference in size of the gearwheels, the greater the difference in speed of revolution.
- Gearwheels can be connected directly, and also indirectly by a belt or chain. The use of gearwheels can reduce the force needed to do work. Gearwheels are features in many machines, sometimes in complex ways (for example, in a mechanical clock or watch).