MCQ Detailed View

The behavior of gases is explained by several gas laws, one of the most important being Boyle’s Law. This law states that for a fixed mass of gas kept at a constant temperature, the pressure of the gas is inversely proportional to its volume. In simple terms, if the volume of a gas is decreased, its pressure will increase, and if the volume is increased, its pressure will decrease, provided the temperature remains unchanged.

Mathematically, Boyle’s Law is expressed as:
P × V = constant
Where:

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  P = pressure of the gas

  
  


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  V = volume of the gas

  
  

This means that when you compress a gas into a smaller container (decreasing volume), the gas molecules are forced into a smaller space. As a result, they collide with the container walls more frequently, causing an increase in pressure. Conversely, allowing the gas to expand into a larger volume reduces these collisions, lowering the pressure.

Real-life examples of Boyle’s Law include:

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  Syringes, where pulling back the plunger increases volume and lowers pressure, drawing fluid in.

  
  


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  Bicycle pumps, where pushing the handle decreases volume, increasing pressure to inflate a tire.

  
  


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  Respiration, where lungs change volume to regulate air pressure during breathing.

  
  

The other answer options are incorrect:

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  Also decrease is wrong because decreasing volume increases pressure.

  
  


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  Remains constant applies only when both temperature and volume are constant.

  
  


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  None of these is incorrect because option 2 is the correct scientific principle.

  
  

This question belongs to Physics because it explains the fundamental relationship between pressure and volume of gases, which is a key part of thermodynamics and kinetic theory of gases.