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Double Slit Interference Fringe Orders Calculator

Defines the integer fringe-order labels used in double-slit interference.

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Formula first

Overview

The symbol m labels the bright-fringe order, while n is the integer order counter used in related interference notation.

Symbols

Variables

m = m

m
Variable

Apply it well

When To Use

When to use: Use this when you need to identify the integer order of a bright or dark fringe.

Why it matters: The order number tells you which interference maximum or minimum you are solving for.

Avoid these traps

Common Mistakes

  • Treating the order as a decimal.
  • Using the wrong starting index for the fringe family.

One free problem

Practice Problem

What order is the central bright fringe in double-slit interference?

contextcentral maximum

Solve for:

Hint: Central bright fringe means zero order.

The full worked solution stays in the interactive walkthrough.

References

Sources

  1. OpenStax University Physics Volume 3, Interference and Diffraction, accessed 2026-04-09
  2. Young, Freedman, University Physics with Modern Physics, 15th ed., Pearson, 2019
  3. University Physics textbooks discussing wave interference (e.g., Young's Double Slit Experiment).
  4. Halliday, Resnick, and Walker, Fundamentals of Physics
  5. Young and Freedman, University Physics
  6. Halliday, Resnick, Walker - Fundamentals of Physics
  7. Hecht, Eugene - Optics
  8. Wikipedia - Double-slit experiment