How does the hydraulics system in a cars brakes work?
Hydraulics can be thought of as liquid levers multiplying the input effort(think of a hydraulic car jack lifting a ton by you cranking a lever),In stead of a collection of solid metal cranks and such connecting all four brakes to one pedal(which would be impossible to get to operate simultaneously)an incompressible fluid links all four brakes to the pedal through a series of small bore pipes.The principle of hydraulics means that applying pressure at the pedal transmits pressure down to the brakes,the fluid wants to burst out but can’t so it moves the piston and pads..A multiplying device known as a servo increases the force applied.That’s why a vehicle that’s being towed while the engine isn’t running has very poor brakes,no servo assist.Car brakes have in effect two master cylinders combined into 1 unit,this is to permit two separate brake circuits,in event of one failing it should be able to stop on the remaining brake circuit.So,1lb of pressure at the pedal means 1lb off pressure/p
