What is Drunk Driving?
Drunk driving is operating a motor vehicle while impaired by alcohol. Most countries enforce a legal blood alcohol concentration (BAC) limit of 0.08% for drivers, with severe penalties for violations.
Drunk driving is illegal when BAC exceeds the legal limit (typically 0.08%), risking injury, death, and criminal penalties including jail and license revocation.
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Step-by-step worked examples
After 3 beers in 1 hour, a 70 kg person has BAC = (3 × 0.6 × 5) / 70 ≈ 0.13%. Legal limit 0.08% — driving is illegal.
Drinks = 3, Weight = 70 kg, Hours = 1 BAC = (3 × 0.6 × 5) / 70 = 9 / 70 ≈ 0.13% 0.13% > 0.08% (illegal)
A driver waits 3 hours after 2 drinks before driving. Is 0.04% BAC legal?
Initial BAC = (2 × 0.6 × 5) / 70 ≈ 0.086% After 3 hours: 0.086 − (3 × 0.015) ≈ 0.041% 0.041% < 0.08% (legal)
Zero-tolerance law for under-21: any BAC > 0.00%. A teen with 0.02% BAC is charged.
Legal limit (under 21) = 0.00% Measured BAC = 0.02% 0.02% > 0.00% (violation)
Flashcards
Quick quiz
Q1.Legal BAC for driving an adult?
Q2.After 1 drink, approximately how long until sober?
Q3.Drunk driving is most dangerous because…
Q4.What applies to under-21 drivers?
The full card deck, worked steps and AI-tutor support for “What is Drunk Driving?” are in Notek — study by hand before your exam.
Common mistakes
A coffee will sober me up quickly. — Correct: Only time metabolizes alcohol. Coffee masks tiredness but does not lower BAC.
Eating food reduces your BAC. — Correct: Food slows alcohol absorption but doesn't eliminate it faster.
Cold air or a shower helps you sober up. — Correct: Only the liver metabolizes alcohol (~1 drink/hour), regardless of temperature.
I'm a skilled driver, so I can drive impaired. — Correct: Alcohol impairs even experienced drivers; BAC affects everyone.
FAQ
What is drunk driving?
Operating a vehicle while impaired by alcohol — typically BAC above 0.08%.
What are the penalties for drunk driving?
Fines, jail time, license suspension/revocation, increased insurance, and possible vehicle impound.
How long after drinking can I drive safely?
A safe rule: wait 1–2 hours per drink. The body metabolizes ~0.015% BAC per hour.
Why is drunk driving so dangerous?
Alcohol impairs vision, reaction time, judgment and motor control — all critical for driving.