We just learned about the Hydraulic Cylinder.
Another type of a machine is a Hydraulic Brake.
In a machine like a car, the brakes that stop the car work by closing tightly and squeezing the wheel to try and slow it down.
The pieces that close are called pistons, and in a hydraulic brake system they are pushed closed by liquids.
There is a tube that is hooked up to the brake, and when a liquid called brake fluid is pushed in, it pushes on the pistons which push on the wheel and close it.
The brake fluid is pushed into the tube from another place, where a metal pole is pushed into the the liquid to push it down into the tube.
So in a hydraulic brake system in a car, when you push your foot down on the brake, it pushes the liquid into the tube which pushes the brakes closed and stops the car.
(from: wikipedia - hydraulic brake)
Kid Facts - Blast from the past: Falcon
