Return to Index

Mirror Equation

Experiment Module

Mirror Equation

Theory & Logic

Theoretical Background

Physics describes the fundamental mechanism of the universe. The Mirror Equation is an essential tool for understanding Mirror Equation in quantitative terms. Calculate focal length f = (do*di)/(do+di).

Mathematical Formulation

The relationship between the variables is governed by the following equation:

Result = (do × di) ÷ (do + di)
Eq 1.1: Governing Formula

Variable Legend

Symbol Parameter Unit
do Object Dist cm
di Image Dist cm

Practical Calculation Example

Problem

Calculating the result when:

  • Object Dist = 100 cm
  • Image Dist = 95 cm

Solution

Substituting into Eq 1.1:

Result = (100 × 95) ÷ (100 + 95)