What is Boyle's Law?

Boyle's Law is a fundamental principle in gas laws, stating that for a fixed amount of gas at a constant temperature, the pressure and volume are inversely proportional. This means that as the pressure on a gas increases, its volume decreases proportionally, and vice versa.

Diagram illustrating Boyle's Law with a piston compressing gas in a cylinder, showing that as volume decreases, pressure increases.

Formula of Boyle's Law

The mathematical relationship for Boyle's Law is:

$$ P_1 V_1=P_2 V_2 $$

Where:

  • p1is the initial pressure of the gas.
  • V1is the initial volume of the gas.
  • P2is the final pressure of the gas.
  • V2is the final volume of the gas.

How to Calculate Using Boyle's Law

To find an unknown variable, you can rearrange the formula. For example, to solve for the final volume ($V_2$):

$$ V_2=\frac{P_1 V_1}{P_2} $$

Example:

A balloon contains 2.5 L of air at a pressure of 1.0 atm. If the balloon is taken underwater where the pressure becomes 3.0 atm, what is the new volume of the air inside? (Assume temperature is constant).

Given:$$P_1=1.0 \text{ atm,} V_1=2.5 \text{ L,} P_2=3.0 \text{ atm}$$

Calculation:

$$ V_2=\frac{1.0 \text{ atm} \times 2.5 \text{ L}}{3.0 \text{ atm}} \approx 0.833 \text{ L} $$

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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.