Students are often introduced to optics in their middle school years. The initial topics that are introduced through their lessons are laws of reflection and refraction of light. In the law of reflection, students do not often question why the angle of incidence is equal to the angle of reflection and why a light ray should follow this specific path. Here we encourage students to question this result and provide an exercise to facilitate instruction regarding specular reflection of light.

1.
H.
Haber
, “
Fermat’s Principle and the Laws of Reflection and Refraction
” (
2009
), http://scipp.ucsc.edu/∼haber/ph5B/fermat09.pdf.
3.
H.
Ray
and
S.
Ray
, “
The easiest proof of Fermat’s principle
,”
Resonance
23
(
8
),
861
869
(
2018
).
4.
R. P.
Feynman
,
R. B.
Leighton
, and
M.
Sands
,
The Feynman Lectures on Physics
, Vol.
I
(
Addison-Wesley
,
Reading, MA
,
1989
), Chap. 26.
5.
See the unequal distance case at TPT Online, 10.1119/10.0006918, under the Supplemental tab.

Supplementary Material

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