Description:
The correct answer is:
✅ 1–5 km/h (or 1–3 mph)
Beaufort Scale: "Light Air" (Force 1)
Wind Speed: 1–5 km/h (0.3–1.5 m/s).
Effects:
Smoke drifts lazily.
Water surfaces appear glassy (no waves).
Category: The weakest measurable wind on the scale.
Why Not the Others?
❌ 10–12 km/h: Force 2 (Light Breeze)—leaves rustle.
❌ 18–21 km/h: Force 3 (Gentle Breeze)—small waves form.
Fun Fact: The Beaufort Scale was invented in 1805 by a British admiral to classify winds for sailors! ⛵🌬️
Bonus: Force 0 is "Calm" (0 km/h, smoke rises vertically). 🚬⬆️