CDL General Knowledge Practice Test 5

Question 1

Which of the following is NOT a required emergency equipment must you have?

Accepted Answer

Glass breaking device

Answer

While a fire extinguisher, warning devices (like reflective triangles), and spare electrical fuses are mandatory emergency equipment for commercial vehicles, a glass breaking device is not a federally required item. Although it might be useful, it's not part of the standard regulatory requirements.

Question 2

Which of the following is a condition in which you should downshift?

Accepted Answer

Before starting down a hill

Answer

Downshifting before starting down a hill is crucial for controlling vehicle speed and preventing brake fade. By engaging a lower gear, the engine provides significant braking power (engine braking), reducing the need for constant use of the service brakes and helping to maintain a safe speed on descents.

Question 3

Where should you place your reflectors when stopped on a un-divided highway or two lane road carrying traffic in both directions?

Accepted Answer

100' behind and ahead of your vehicle and within 10' of the front or rear corner

Answer

On an undivided highway or two-lane road with traffic in both directions, warning devices must alert traffic from both directions. The correct placement is one reflector within 10 feet of the front or rear corner of the vehicle, and then one 100 feet behind and one 100 feet ahead of the vehicle.

Question 4

Which of the following represents the best way to make a right turn if you have a large vehicle that cannot make the turn without swinging into another lane.

Accepted Answer

Diagram C

Answer

For large vehicles, Diagram C typically illustrates the 'buttonhook' or 'jug handle' right turn. This technique involves swinging wide *after* entering the intersection, allowing the rear of the trailer to clear the corner without hitting the curb or other objects, and without swinging into the left lane before the turn.

Question 5

________ can cause lack of braking power, wheel lockups, pulling to one side or the other, and jackknifing.

Accepted Answer

Wet brakes

Answer

Wet brakes can significantly reduce friction between the brake linings and drums/rotors, leading to a lack of braking power. This can cause uneven braking, resulting in wheel lockups, the vehicle pulling to one side, or even jackknifing in articulated vehicles, making them extremely dangerous.

CDL Practice Test

CDL Practice Test

CDL General Knowledge Practice Test 5