CAPF AC 2021 Q38: Geography – Atmosphere & Climatology
The speed of the wind is measured by
- (a) wind vane
- (b) wind rose
- (c) barometer
- (d) anemometer
Answer: (d) anemometer
Explanation
Weather instruments
How to think: separate speed from direction.
The anemometer measures wind speed.
The wind vane shows wind direction.
| Instrument or diagram | What it tells |
|---|---|
| Anemometer | Speed of the wind |
| Wind vane | Direction of the wind |
| Wind rose | A diagram showing how often the wind blows from each direction |
| Barometer | Atmospheric pressure |
| Hygrometer | Humidity |
| Rain gauge | Rainfall |
Answer: (d) anemometer.
Why each option is right or wrong
- (a) Incorrect. A wind vane shows the direction of the wind, not its speed.
- (b) Incorrect. A wind rose is a diagram of wind direction and frequency, not an instrument.
- (c) Incorrect. A barometer measures atmospheric pressure.
- (d) CORRECT. An anemometer measures the speed of the wind.
Key point
Anemometer: wind speed. Wind vane: wind direction. Barometer: pressure. Hygrometer: humidity. Rain gauge: rainfall. The Beaufort scale estimates wind force.
Remember
Anemometer = speed, wind vane = direction.
Common mistakes
- Mixing up the wind vane (direction) with the anemometer (speed).
- Thinking a wind rose is an instrument; it is only a diagram on a map.
- Marking the barometer because pressure differences cause winds.
Exam tip
Educated guess: anemos is the Greek word for wind and meter means measure. A vane only points; it cannot measure.
Sources
- NCERT Class XI Geography — Practical Work in Geography (Weather Instruments, Maps and Charts)
- NCERT Class VII Geography — Air