Objects and Images

The focal length (f) is related to the distance from the lens to the object (Do) and the distance from the lens to the image that is created (Di) by this equation:

Object Image Formula

Compute Do or Di, given the values of the other variables in the equation above.

Subject: Mathematics
Topics: Algebra--Expressions and Equations
Grades: 6 - 12
Knowledge and Skills:
- Can evaluate expressions by substituting values for variables
- Can simplify expressions using correct order of operations
- Can do basic operations on both sides of an equation in such a way as to preserve the equality

Download Teacher Guide: Objects and Images (PDF)
Download Student Lesson: Objects and Images (PDF)

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