Which of the following instruments is used for measuring the speed of wind?

Step 1: Analyze the question The question asks which instrument measures the speed of wind. The key word is "speed," not direction, pressure, or humidity.

Step 2: Explain the concepts Let's look at what each instrument measures:

• Anemometer: measures wind speed. It usually has cup-shaped arms that spin faster when the wind blows harder. The name comes from the Greek anemos, meaning "wind."
• Barometer: measures atmospheric pressure.
• Hygrometer: measures humidity, the amount of water vapour in the air.
• Manometer: measures the pressure of gases or liquids in a closed system.
• Windvane: shows wind direction, not speed.

Step 3: Solution

• Wind speed is measured by the anemometer, which matches option A.
• The windvane (E) is the closest distractor. It deals with wind, but it tells you where the wind is coming from, not how fast it is blowing.
• The other options measure pressure or humidity.

Step 4: Answer The correct option is A. anemometer.

Tip: Remember "Anemometer = Air speed" (both start with A), and "Vane = View direction" (both start with V). In Biology and Geography papers, matching the instrument to what it measures is a common question type:

• Barometer → pressure
• Hygrometer → humidity
• Thermometer → temperature
• Rain gauge → rainfall
• Anemometer → wind speed
• Windvane → wind direction