MCQ Detailed View

A hygrometer is a scientific instrument used to measure the humidity of air, which refers to the amount of water vapor present in the atmosphere. Humidity plays a crucial role in weather patterns, human comfort, plant growth, and many industrial processes, making the hygrometer an essential tool in both everyday life and scientific research.There are different types of hygrometers, but all of them are designed to detect changes in moisture levels in the air. The most common types include:

1. 
   

   Mechanical hygrometers, which use materials like hair or special fibers that expand or contract depending on the humidity level. This physical change moves a needle on a scale to display the humidity percentage.

   
   


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   Electronic hygrometers, which use sensors to measure relative humidity and often display results digitally. These are widely used in weather stations, homes, and laboratories.

   
   


3. 
   

   Psychrometers, which consist of two thermometers (one dry bulb and one wet bulb) to determine humidity based on temperature differences.

   
   

Humidity is expressed as relative humidity (RH), a percentage that shows how much water vapor is in the air compared to the maximum amount the air can hold at a given temperature. For example, 50% RH means the air is holding half of its maximum moisture capacity.

Other options in the question refer to unrelated measurements:

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  Speed of sound is measured using specialized acoustic devices.

  
  


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  Density of milk is checked with a lactometer.

  
  


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  Specific gravity of liquids is measured using a hydrometer.

  
  

By understanding what a hygrometer does, students learn about atmospheric science, weather forecasting, and physical measurement instruments, which are important concepts in Physics and environmental studies. This instrument helps predict weather conditions, control indoor climates, and maintain proper conditions in industries such as food storage, pharmaceuticals, and agriculture.