Calculate the final-to-initial ratio from measured length, area, or volume. Choose a thermal task to estimate size change, initial size, or coefficient from temperatures and material data.

Compare final size with initial size.

Thermal mode assumes free expansion, constant coefficient, and no phase change. Linear-to-area/volume conversion assumes an isotropic solid and small fractional changes.

Expansion Ratio Formula

The following formula is used to calculate the expansion ratio.

ER = Vf / Vแตข

Variables:

  • ER is the expansion ratio
  • Vf is the final volume
  • Vi is the initial volume

To calculate the expansion ratio, divide the final volume by the initial volume. For length or area, use the corresponding final and initial sizes. Thermal tasks use ฮ”size = c ร— initial size ร— ฮ”T with a constant coefficient and no phase change; linear-to-area and linear-to-volume conversions assume an isotropic solid.

What is an Expansion Ratio?

The expansion ratio is a measure of how much a substance expands when it undergoes a phase change or a chemical reaction. It is the ratio of the final volume to the initial volume. This concept is commonly used in various fields such as thermodynamics, engineering, and material science to understand the behavior of substances under different conditions.

How to Calculate Expansion Ratio?

The following steps outline how to calculate the Expansion Ratio.

  1. First, determine the initial volume (Vi).
  2. Next, determine the final volume (Vf).
  3. Finally, calculate the expansion ratio using the formula ER = Vf / Vi.
  4. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Initial Volume (Vi) = 2 mยณ

Final Volume (Vf) = 6 mยณ. In โ€œRatio from measured sizes,โ€ these values give ER = 6 / 2 = 3 : 1, a 200% increase.