Question

In a vacuum suspended unit, when the brakes are on, the piston and the diaphragm has on both sides of it
(A) Atmospheric pressure
(B) Vacuum
(C) Hydraulic pressure
(D) Air pressure

Answer 1

Hint : In order to find which pressure acts on both sides of the piston and the diaphragm, we will try to understand the basic working of power brakes and then we will determine the correct type of pressure which acts in the given case. Vacuum is nothing, just space with the absence of any kind of matter completely.

Complete Step By Step Answer:
The power brakes are designed in such a way that they use the power from the engine to increase braking efficiency and reduce the driver’s pedal effort. Power brakes can use either hydraulic pressure, air pressure, vacuum or gearbox-drive assistance.
Now, when the brakes are applied, a little vacuum is just formed on both sides of the booster and as a result the atmospheric pressure pushes on and it moves the diaphragm.
In this case, in a vacuum suspended unit when the brakes of the system are on the piston and the diaphragm both has atmospheric pressure on its both sides. Therefore we can say that it’s the atmospheric pressure which is on both sides of the piston and the diaphragm.
Hence, the correct option is (A) Atmospheric pressure.

Note :
It must be remembered that power based brakes are designed in a system in such a way that it reduces the human effort while stopping a vehicle. It’s important to remember that the unit in which power is measured generally is called Watts and power is the amount of energy consumed per unit time, whereas the unit in which energy is generally measured is called Joules.