Which phenomenon describes wind accelerating as it passes through a gap?

• A. Venturi effect
• B. Headwind effect
• C. Sea breeze
• D. Funnel effect

Answer: (D)

Wind accelerates through a gap because the flow is forced to pass through a narrower opening, so the air must move faster to carry the same amount of air through. As the cross-sectional area decreases, velocity increases, and pressure drops along the constriction. This is described by the Venturi effect. In a kayaking context, you can feel stronger gusts or abrupt increases in wind when you pass between rocks or cliffs. The other ideas don’t capture this specific mechanism: a headwind describes wind blowing toward you and doesn’t imply acceleration through a gap; a sea breeze is a coastal, daily wind pattern driven by temperature differences, not the constricted-flow acceleration; funnel effect isn’t the standard term for this physical process. The Venturi effect best explains why wind speeds up as it goes through a gap.