Stopping distance parts — Louisiana Permit Test
Stopping distance parts on the Louisiana permit test — 5 rules, each with the reason behind it and a question on it while it is fresh.
The rules
The average perception time for an alert driver is 3/4 second to 1 second.
Even before your foot moves, your car keeps going while your brain works out what it sees.
The average perception time for an alert driver is ¾ second to 1 second.
Reaction distance is how far you travel before you physically hit the brakes; at 50 mph this is 55 feet.
The car is still at full speed while your foot moves to the brake, and that gap adds up fast.
At 50 mph this accounts for 55 feet traveled.
Braking distance at 50 mph on dry pavement with good brakes can be about 158 feet.
Once the brakes are on, a car at 50 mph still slides about half a football field.
At 50 mph on dry pavement with good brakes, it can take about 158 feet.
Total stopping distance at 50 mph, counting perception, reaction and braking, is a minimum of 268 feet.
Seeing, reacting and braking all add up, so stopping takes far longer than most drivers think.
At 50 mph, your vehicle will travel a minimum of 268 feet.
Total stopping distance includes perception distance, reaction distance and braking distance.
Each part adds feet to the stop, so leaving one out makes you think you can stop sooner than you can.
with everything considered, including perception distance, reaction distance and braking distance,
On the test
What is the average perception time for an alert driver?
About 3/4 to 1 second. Even before your foot moves, your car keeps going while your brain works out what it sees. Class D & E Driver's Guide, p.64: “The average perception time for an alert driver is ¾ second to 1 second.”
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
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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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- Do the work, fail the real exam, and we refund you.
Where these come from
Every rule here is checked against Class D & E Driver's Guide, published by the Louisiana Department of Public Safety, and against the state code itself. Last checked 2026-10-04.
- src/assets/drivers-manuals/LA.pdf (Class D & E Driver's Guide, DPSMV2052 (R08/25), Louisiana Office of Motor Vehicles, retrieved 2026-09-14; sha256 pinned in SOURCES.json)
- src/assets/drivers-manuals/LA.pages.txt (the plain pdftotext fixture every citation here was cut from and verified against; sha256 pinned in SOURCES.json)
- src/assets/drivers-manuals/LA-exam.html (the OMV's Permits page, https://expresslane.la.gov/omv/drivers/personal-driver-s-licenses/permits/, archived 2026-10-04; the 40-question count)
- https://expresslane.la.gov/omv/resources/driver-manuals/
- https://expresslane.la.gov/omv/drivers/personal-driver-s-licenses/new-licenses/ (read 2026-10-04; "An 80% is the minimum passing score for the knowledge test.")