T-Junction at Dusk with a Stop Sign
You are driving a Category B pickup east on a two-lane city road in Phnom Penh at 18:40. Light rain has made the asphalt glossy, and the sun has set. Your road ends at a T-junction with a larger priority road. Your lane has a red octagonal STOP sign and a faded stop line partly hidden by water. You want to turn left. A motorcycle is approaching from your right on the priority road at about 45 km/h, roughly 80 metres away; its headlight is off. A car behind you is close and its driver taps the horn. Your passenger says, “Go-it is far enough.” You must cross the near lane and enter the far lane. Rain reduces visibility, and pedestrians are waiting on the far corner. The motorcycle rider is wearing dark clothing.
1. What must you do at the stop line, and who has priority?
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- A STOP sign requires a complete stop, not a rolling check. Stop behind the faded line; if it is not visible, stop before the edge of the priority road where you can see and be seen.
- Traffic on the priority road has right-of-way. The motorcycle approaching from your right is on that road, so it has priority over your left turn. Your turn crosses its path.
- The close car behind and the passenger's advice do not create a legal right to enter. Signal left early, keep the wheels straight until you move, and wait for a safe gap.
- Rain and the rider's dark clothing increase the risk. The motorcycle's missing headlight does not give you priority; if anything, it makes the rider harder to see.
2. How should you judge the 80 m gap, and what makes it unsafe?
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- At 45 km/h the motorcycle covers about 12.5 m each second, so 80 m is roughly 6.4 seconds at constant speed. That sounds long, but it is not the whole calculation.
- You must complete the stop, select a gear, cross the near lane, and clear the far lane without forcing the motorcycle to brake. Wet asphalt lengthens your own braking and reduces the motorcycle's margin.
- The rider's headlight is off and clothing is dark, so your ability to judge speed and distance is poor. Pedestrians on the far corner may make you stop mid-turn.
- If the gap requires the rider to adjust speed, it is not safe. Wait; the car behind must stop. Do not wave it around you.
3. The motorcycle slows and flashes its headlights. What does that change?
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- A headlight flash is ambiguous: it may mean “I yield,” “I am here,” or a warning. It does not transfer right-of-way by itself.
- Keep the stop until the motorcycle clearly slows and stops, or until it passes. Watch the front wheel and the rider's body language, not only the lamp.
- If the rider stops, make eye contact if possible, check the far lane and pedestrians, then proceed decisively without lingering in the junction.
- If the rider continues, wait. A mistaken assumption here causes a left-turn collision, which is a common severe crash pattern.