Which meteorological instrument is specifically used to measure the speed of wind in the atmosphere?

Introduction / Context:
Weather stations and meteorological departments use different instruments to measure various atmospheric quantities such as temperature, pressure, humidity and wind speed. Knowing which instrument corresponds to which quantity is a common requirement in general knowledge and basic science exams. This question asks you to identify the instrument used specifically for measuring wind speed.

Given Data / Assumptions:

• The quantity of interest is wind speed in the atmosphere.
• Options include anemometer, inclinometer, fathometer and calorimeter.
• We assume standard instrument definitions in meteorology and physics.

Concept / Approach:
An anemometer is a meteorological instrument designed to measure wind speed, and sometimes wind direction together with other devices. Traditional cup anemometers use rotating cups that spin faster as wind speed increases. Modern anemometers may use ultrasonic sensors. Inclinometers measure angles of slope or tilt, fathometers measure water depth using sound waves, and calorimeters measure heat changes in thermal experiments. Therefore, anemometer is the correct instrument for wind speed measurement.

Step-by-Step Solution:
Step 1: Recall that wind speed is a basic weather variable used in forecasting storms, aviation safety and marine navigation. Step 2: Anemometers are routinely seen in images of weather stations as instruments with rotating cups or propellers. Step 3: The rotation rate of the cups or propeller is calibrated to give wind speed in units such as m/s or km/h. Step 4: Inclinometers are used to measure slope or tilt angles in engineering and surveying, not wind speed. Step 5: Fathometers are echo sounding devices that send sound waves downward in water to measure depth beneath a ship. Step 6: Calorimeters are laboratory instruments used to measure amounts of heat in physical or chemical processes. Step 7: Thus, the only instrument designed for wind speed measurement among the options is the anemometer.

Verification / Alternative check:
Weather reports from meteorological departments often reference data from anemometers when describing wind speed at various locations. Aviation and marine weather stations also rely on anemometers to monitor conditions for safe operations. Textbooks and encyclopedias consistently define an anemometer as a wind speed measuring device, while inclinometer, fathometer and calorimeter have completely different uses. This confirms that anemometer is the correct answer.

Why Other Options Are Wrong:
Inclinometer measures inclination or tilt angles and is used in civil engineering and geology. Fathometer measures depth of water from a ship to the sea bottom using echo sounding. Calorimeter measures heat quantities in experiments and is not connected to wind speed.

Common Pitfalls:
Because all the options end with the suffix meter, indicating measurement, students may confuse their functions. A simple memory aid is to associate anemo with wind, fathom with depth, inclin with inclination and calor with heat. Keeping these associations clear prevents confusion and allows you to answer such instrument questions quickly and accurately.

Final Answer:
The instrument used to measure wind speed is the Anemometer.