Plane mirror

<h2 id="preparation">Preparation</h2>

<p>A plane mirror is made using some highly reflecting and polished surface such as a <a href="/facts/Silver/xXe41BGg">silver</a> or <a href="/facts/Aluminum/7wmR8jYE">aluminium</a> surface in a process called <a href="/facts/Silvering/oEtIzfVv">silvering</a>.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> After silvering, a thin layer of red lead oxide is applied at the back of the mirror. The reflecting surface reflects most of the light striking it as long as the surface remains uncontaminated by <a href="/facts/Tarnish/GCskvFrN">tarnishing</a> or <a href="/facts/Oxidation/Pyd5RVcj">oxidation</a>. Most modern plane mirrors are designed with a thin piece of <a href="/facts/Plate_glass/6NUwUyBE">plate glass</a> that protects and strengthens the mirror surface and helps prevent tarnishing. Historically, mirrors were simply flat pieces of <a href="/facts/Polishing/SqMg0yh9">polished</a> <a href="/facts/Copper/I8PEE8oX">copper</a>, <a href="/facts/Obsidian/GW1DI93A">obsidian</a>, <a href="/facts/Brass/pe8EHk6x">brass</a>, or a precious metal. Mirrors made from <a href="/facts/Liquid/t9GkLWzt">liquid</a> also exist, as the elements <a href="/facts/Gallium/EucevDs9">gallium</a> and <a href="/facts/Mercury_(element)/WlxfoHva">mercury</a> are both highly reflective in their liquid state.
</p>
<h2 id="relation-to-curved-mirrors">Relation to curved mirrors</h2>
<p>Mathematically, a plane mirror can be considered to be the <a href="/facts/Limit_(mathematics)/j8JBhj4e">limit</a> of either a concave or a convex spherical <a href="/facts/Curved_mirror/X1c0aVmK">curved mirror</a> as the radius, and therefore the <a href="/facts/Focal_length/brGIUkEY">focal length</a> becomes infinity.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a>
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<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Geometrical_optics/gIFu84Tm">Geometrical optics</a></li>
<li><a href="/facts/Specular_reflection/dwVIqLVb">Specular reflection</a></li>
<li><a href="/facts/Chinese_magic_mirror/gRh5sr27">Chinese magic mirror</a></li>
<li><a href="/facts/Law_of_reflection/dwVIqLVb">Law of reflection</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Moulton, Glen E. (April 2013). CliffsNotes Praxis II: Middle School Science (0439). Houghton Mifflin Harcourt. ISBN 978-1118163979. <a href="978-1118163979" target="_blank">978-1118163979</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Saha, Swapan K. (2007). Diffraction-Limited Imaging with Large and Moderate Telescopes. World Scientific. ISBN 9789812708885. <a href="9789812708885" target="_blank">9789812708885</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>Giordano, Nicholas (2012-01-01). College Physics. Cengage Learning. ISBN 978-1111570989. <a href="978-1111570989" target="_blank">978-1111570989</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>Katz, Debora M. (2016-01-01). Physics for Scientists and Engineers: Foundations and Connections. Cengage Learning. ISBN 9781337026369. <a href="9781337026369" target="_blank">9781337026369</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
<li id="fn:5"><p>"2.2 Spherical Mirrors - University Physics Volume 3 | OpenStax". <a href="https://openstax.org/books/university-physics-volume-3/pages/2-2-spherical-mirrors" target="_blank">https://openstax.org/books/university-physics-volume-3/pages/2-2-spherical-mirrors</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li>
<li id="fn:6"><p>Kołakowski, Leszek (September 2000). Science and Technology Encyclopedia. University of Chicago Press. ISBN 9780226742670. <a href="9780226742670" target="_blank">9780226742670</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li>
<li id="fn:7"><p>Katz, Debora M. (2016-01-01). Physics for Scientists and Engineers: Foundations and Connections. Cengage Learning. ISBN 9781337026369. <a href="9781337026369" target="_blank">9781337026369</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li>
</ol>

Plane mirror open-in-new

Plane mirror