Truck stopping distance — District of Columbia Permit Test
Truck stopping distance on the District of Columbia permit test — 2 rules, each with the reason behind it and a question on it while it is fresh.
The rules
A car traveling 60 mph can stop in about 366 feet.
The truck needs more road than you do, so cutting in and braking in front of it leaves it nowhere to stop.
A car traveling 60 miles per hour can stop in about 366 feet.
A truck traveling 60 mph takes more than 400 feet to stop.
A truck's weight keeps it rolling long after the driver hits the brakes.
A truck traveling at the same speed takes more than 400 feet to stop.
On the test
At 60 mph, about how far does a car need to stop?
About 366 feet. The truck needs more road than you do, so cutting in and braking in front of it leaves it nowhere to stop. DC Driver Manual, p.65: “A car traveling 60 miles per hour can stop in about 366 feet.”
How this works
Most practice tests hand you a bank of questions and leave the manual somewhere else. This one puts them together.
You read one law and the reason behind it, then answer a question on that law while it is still fresh. Get it right and you move on; get it wrong and you have found the gap while it is cheap to fix, not on the morning of the exam.
Learning one rule at a time, and proving it immediately, is what turns a manual you skimmed into something you actually know — and it makes studying feel like getting somewhere rather than like waiting to find out.
What it costs
- One payment, once — not a subscription. Nothing renews and there is nothing to cancel, for an exam you sit one time.
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- Paying opens the rest of the cards, unlimited full-length practice tests, and retests built from exactly the questions you got wrong.
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All District of Columbia permit topics
Where these come from
Every rule here is checked against DC Driver Manual, published by the District of Columbia Department of Motor Vehicles, and against the state code itself. Last checked 2026-10-05.
- src/assets/drivers-manuals/DC.pdf (DC Driver Manual (English), Rev. 7/29/2021, District of Columbia Department of Motor Vehicles, fetched 2026-10-05 from the Wayback Machine's original-bytes capture of dmv.dc.gov; sha256 pinned in SOURCES.json)
- src/assets/drivers-manuals/DC.pages.txt (the plain pdftotext fixture every citation here was cut from and verified against; sha256 pinned in SOURCES.json)
- https://dmv.dc.gov/publication/dc-dmv-automobile-driver-manual (read 2026-10-05; links only the 2023 Issuu flipbooks)
- https://issuu.com/dcdmv/docs/dc_dmv_driver_manual_english_revised_final (the current 2023 edition, read 2026-10-05 from its public page images to diff against the pinned edition; not pinnable)
- https://dmv.dc.gov/service/knowledge-tests (read 2026-10-05; states no count or mark for the knowledge test)
- https://dcregs.dc.gov/Common/DCMR/RuleList.aspx?ChapterNum=18-1 (18 DCMR chapter 1, sections 100-114, read 2026-10-05; section 104 sets what the examination covers and states no figure)
- https://code.dccouncil.gov/us/dc/council/code/sections/50-1401.01 (D.C. Code 50-1401.01, read 2026-10-05; requires a knowledge examination and states no figure)