ch2 heavy vehicle braking

Question 1

What’s the final factor that will determine if the vehicle will move?

Answer 1

traction between the tires
and the road surface

Question 2

How is brake heat dissipated?

Answer 2

The heat is absorbed and dissipated into the atmosphere, primarily through
the brake drums/rotors.

Question 3

If the weight of the vehicle is doubled, how many times must the
stopping power be increased?

Answer 3

2 ✕ vehicle weight requires 2 ✕ the stopping power

Question 4

What causes brake fade?

Answer 4

As
brake drums heat up, they expand away from the brake linings. Too much
heat can result in brake fade, brake damage and/or brake failure.

Question 5

What can cause jackknifing?

Answer 5

A full jackknife occurs when
a tractor and the trailer form
an angle of 90 degrees or
less, relative to one another.

Question 6

What’s the difference between ABS and ATC?

Answer 6

ABS is an addition to a normal air brake system. It helps prevent wheel lockup
or skids caused by overbraking on slippery road surfaces, Automatic Traction Control (ATC) is an optional addition to an ABS system. It
uses the pulsating signal from the speed sensors to detect loss of drive wheel
traction on slippery road surfaces.

Question 7

What’s one of the hazards of stopping a tractor/trailer combination?

Answer 7

Icy roads, water on roadways, downgrade etc.

Question 8

When should a retarding device be used?

Answer 8

Retarders are designed to provide auxiliary slowing of the vehicle, such as
for controlling the speed on long downgrades without the use of the main
braking system.

Question 9

What’s brake lag time?

Answer 9

the time between when you apply the brake and when
the brakes begin to function