Alabama CDL General Knowledge Practice Test # 4

Question 1

DOUBLING YOUR SPEED HAS WHAT EFFECT ON BRAKING DISTANCE?

Accepted Answer

Twice the speed = four times the stopping distance

Answer

Doubling your speed has a significant effect on braking distance, increasing it by four times. This is because kinetic energy, which must be dissipated by the brakes, increases with the square of the speed. Therefore, if you double your speed, your vehicle has four times the kinetic energy, requiring four times the braking distance to stop.

Question 2

COMMON MEDICINES FOR COLDS CAN MAKE YOU SLEEPY.

Accepted Answer

TRUE

Answer

This is true. Many common over-the-counter medicines for colds, allergies, or pain relief contain ingredients that can cause drowsiness, dizziness, or impaired judgment. Driving while under the influence of these medications can be as dangerous as driving while fatigued or impaired by alcohol. Always read warning labels and understand the side effects of any medication before driving.

Question 3

WHAT ARE THE THREE RULES FOR USING YOUR TURN SIGNALS?

Accepted Answer

1. Signal early 2. Signal continuously 3. Make sure the signal turns off after the turn is completed

Answer

The three essential rules for using your turn signals are to signal early, signal continuously, and ensure the signal turns off after the turn is completed. Signaling early gives other drivers ample warning of your intentions. Signaling continuously ensures your intentions remain clear throughout the maneuver. Making sure the signal turns off prevents confusion for other drivers who might think you are planning another turn.

Question 4

IF YOU ARE DRIVING A 30-FOOT VEHICLE AT 55 MPH, HOW MANY SECONDS OF FOLLOWING DISTANCE SHOULD YOU ALLOW?

Accepted Answer

4 seconds

Answer

For commercial vehicles, a common rule of thumb for following distance is one second for every 10 feet of vehicle length, plus an additional second for speeds over 40 mph. For a 30-foot vehicle, that's 3 seconds (30 feet / 10 feet/second). Since you're traveling at 55 mph (over 40 mph), you add an extra second, making the total recommended following distance 4 seconds.

Question 5

IF YOU SWING WIDE TO THE LEFT BEFORE TURNING RIGHT, ANOTHER DRIVER MAY TRY TO PASS YOU ON THE RIGHT. TRUE OR FALSE?

Accepted Answer

TRUE

Answer

This statement is true. When a long vehicle swings wide to the left before making a right turn, it creates a large gap on its right side. Other drivers, especially those unaware of the challenges of turning a long vehicle, might mistakenly interpret this gap as an invitation to pass on the right, leading to a dangerous collision. It's crucial for CDL drivers to be aware of this risk and block the lane if necessary.

CDL Practice Test

CDL Practice Test

Alabama CDL General Knowledge Practice Test # 4