FREE Air Brake MCQ Questions and Answers

Question 1

How much force is applied to the push rod in a type 30 brake chamber when a 40 PSI brake application is made?

Accepted Answer

1200 PSI

Answer

70 PSI

Answer

400 PSI

Answer

There is no such thing as a type 30 brake chamber

Question 2

When the air system reaches operational pressure, what does the compressor do?

Accepted Answer

Goes into an unloaded stage

Answer

It has an internal cooling system

Answer

Temporarily stops running

Answer

Nothing. The compressor is supposed to run hot

Question 3

Between what two pressures should reservoir pressure be maintained?

Accepted Answer

80 (552 kPa) psi to 135 psi (930 kPa).

Answer

100 (689 kPa) psi to 125 psi.

Answer

50 psi (345 kPa) to 90 psi (620 kPa).

Answer

105 (724 kPa) psi to 150 psi (1034 kPa).

Question 4

When conducting a build-up test on the compressor, what pressure do you start at?

Accepted Answer

50 psi (345 kPa).

Answer

100 psi (690 kPa).

Answer

85 psi (587 kPa).

Answer

When the low-air warning activates.

Question 5

What is the lowest pressure at which the governor should trigger the compressor to resume its pumping phase?

Accepted Answer

80 psi (552 kPa).

Answer

105 psi (724 kPa).

Answer

60 psi (414 kPa).

Answer

65 psi (448 kPa).

Question 6

What is a parking brake with a DD3 safety actuator?

Accepted Answer

A caging device.

Answer

A spring brake lock.

Answer

An air-operated parking brake.

Answer

An automatic park brake.

Question 7

Which three fundamental brake types are there?

Accepted Answer

S cam brakes, disc brakes and wedge brakes.

Answer

Drum brakes, disc brakes and wedge brakes.

Answer

S cam brakes, disc brakes and friction brakes.

Answer

Rotary brakes, disc brakes and wedge brakes.

Question 8

Air loss shouldn't be more than when performing an air leak test in a single unit at maximum air pressure.

Accepted Answer

3 psi (21 kPa).

Answer

4 psi (28 kPa).

Answer

6 psi (41 kPa).

Answer

2 psi (14 kPa).

Question 9

What type of pressure holds the parking or emergency brakes on trucks and buses in place?

Accepted Answer

Spring pressure

Answer

Fluid pressure

Answer

Atmospheric pressure

Answer

Air pressure

Question 10

What kind of gradient should you park on in order to check the manual slack adjusters of the S-CAM brakes for free play?

Accepted Answer

Park on level ground, chock the wheels and release the parking brakes

Answer

Level ground and apply the parking brake

Answer

Park on a slight grade, release the parking brakes and apply the service brake watching your vehicle movement

Answer

Park on level ground, drain off the air pressure before checking the adjustment