Gears Concept Worm gears are used when a change in the direction in motion is required.
Worm gears act like screws and provide a continuous motion.
In the sample construction below, a force on the worm gear will be changed when connected to a wheel gear. This construction might be used to turn the wheels on a model car. Assemble a wheel and worm gear as pictured to the right. Turn the axle of the worm gear and then turn the axle on the wheel gear. Record your observations in the space below.