Driving SafelyCâu 57 / 60
Why should you generally avoid using the trailer hand valve (trolley/spike valve) to control the vehicle in normal driving?
a.Applying only the trailer brakes can cause the trailer to skid and jackknife
b.It turns off the headlights
c.It raises the landing gear
d.It disconnects the air lines
Giải thích
Using the trailer hand valve alone applies only the trailer brakes, which can lock the trailer wheels and cause a skid or jackknife, especially on slippery roads. Normal braking should use the foot brake, which applies brakes on all wheels together. The hand valve is not a substitute for the service brakes.
Luyện miễn phí toàn bộ 60 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- When driving a combination vehicle on a curved highway exit ramp, what should you do?
- How does the trailer respond to steering inputs compared to the tractor, and why does this matter?
- What is the safest way to brake in a combination vehicle to avoid a skid?
- When changing lanes or merging in a combination vehicle, why must you allow extra space and time?
- On a slippery road, how should you adjust your driving in a combination vehicle to prevent skids?
- Why is it important to check your mirrors frequently when driving a combination vehicle?
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Đội Ngũ Biên Tập PrepPass · Đối chiếu với CDL Combination Vehicles Knowledge Test · Quy trình kiểm tra