Understanding Charles's Law

Charles's Law, also known as the law of volumes, is a fundamental experimental gas law. It describes how gases tend to expand when heated. Formulated by the French scientist Jacques Charles in 1787, the law states that for a fixed mass of an ideal gas at constant pressure, the volume is directly proportional to its absolute temperature.

This means that as the temperature of a gas increases, its volume increases proportionally, and as the temperature decreases, the volume also decreases, provided the pressure and the amount of gas remain constant.

The Formula for Charles's Law

The relationship described by Charles's Law can be expressed mathematically. When comparing the same substance under two different conditions, the formula is:

$$\frac{V_1}{T_1}=\frac{V_2}{T_2}$$

  • \(V_1\)is the initial volume of the gas.
  • \(T_1\)is the initial absolute temperature of the gas (in Kelvin).
  • \(V_2\)is the final volume of the gas.
  • \(T_2\)is the final absolute temperature of the gas (in Kelvin).

Important Note:The temperature must always be in an absolute scale like Kelvin (K) for the calculation to be correct. Our calculator handles the conversion for you if you input Celsius (°C) or Fahrenheit (°F).

How to Use This Calculator

This calculator is designed for ease of use and flexibility. It allows you to solve for any of the four variables in the Charles's Law equation.

  1. Enter Known Values:Fill in any three of the four input fields (Initial Volume, Initial Temperature, Final Volume, Final Temperature).
  2. Select Units:Choose the appropriate unit for each value from the dropdown menus.
  3. View Instant Result:The calculator will automatically compute the fourth value in real-time. The calculated field will be highlighted in green and become read-only.
  4. Dynamic Updates:You can change any of the source values or even the unit of the result field, and the answer will update instantly.
  5. Review the Solution:A detailed, step-by-step breakdown of the calculation is provided below the calculator.
  6. Clear Values:Click the "Clear Values" button to reset all number fields and start a new calculation while keeping your selected units.
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Mr. Singh

Mr. Singh is a passionate educator and skilled writer who brings science to life. With a Master's in Physics and years of teaching, he combines 5+ years of coding and content creation expertise to make complex ideas engaging for everyone.