1. Ch 14 - Hydraulics

2. Hydraulic Devices
If there are no outside forces (like gravity) acting on a fluid, the pressure exerted by the fluid will be the same throughout, and in all direction.
This fact allows hydraulic devices to work.

3. Try pushing a stopper into a bottle full of water

4. What happens?

5. The pressure applied to the water by the stopper acts equally in all directions, including up!

6. Hydraulic Devices
produce enormous forces with the application of only a very small force
hydraulic devices multiply forces
example = hydraulic brakes on a car

7. Allows us to lift and rotate people without effort
or stop cars just by pushing a brake pedal

8. How it Works:

9. 1. A small force is applied to the smaller piston.#1

10. 2. The pressure created by the force pushes against the liquid.#2

11. 3. The piston moves a large distance as it presses on the liquid.#3

12. 4. The pressure is transmitted equally throughout the liquid.#4

13. 5. The transmitted pressure pushes upward against the larger piston, but over a smaller distance.#5

14. 6. The pressure on every square cm of the larger piston is equal to the pressure on every square cm.#6

15. 7. Since the # of square cm (or area) is greater on the larger piston, the force is greater.#7

18. Some animals use hydraulics in order to move.
These animals have fluid filled bodies which allow them to use hydraulics.

19. Things to Remember The pressure is equal in each piston.
Force is calculated by multiplying the pressure times the area.
There is a direct ratio between the area of one piston & the length of the movement of the other piston.