1. GEARS:

2. Gears Gears are teeth on a wheel and axel.
The teeth of one gear fit between the teeth of another gear.

3. Gears
When one gear turns, the other can be made to turn faster, slower or in another direction.
The gears on a clock allow the three hands to move around the face of the clock at different speeds.

4. Gears

5. Gears The wheel that moved first is called the driving gear.
Usually the driving gear is moved by a person or a motor.

6. Gears
The wheel that is moved by the driving gear is called the driven gear.

7. Gears
Different sizes and arrangements of gears are used to make wheels turn faster, slower or in different directions.

8. Gears
A large driving gear makes a small driven gear move faster, but in the opposite direction.
Hand driver drills use this combination of gears to make them spin quickly.

9. Gears
A small driving gear makes a large driven gear move slower but in the opposite direction.
This arrangement acts as a force multiplier.
It is used to move large loads with a small effort.

10. Gears
Pairs of gears the same size change the direction of turning without changing the speed.

11. Gears
Bevel gears are gears that are at right angles to each other and can change vertical motion into horizontal motion.

12. Gears
Rack and pinion gears consist of a flat row of teeth called a rack and a circular gear wheel.