18.1 mirrors

18.1 Mirrors18.1 MirrorsKatie HannaKatie Hanna

MirrorsMirrors

Mirrors are the oldest optical instruments. Mirrors are the oldest optical instruments. Prehistoric humans saw their faces Prehistoric humans saw their faces

reflected in the quiet water of lakes or reflected in the quiet water of lakes or ponds. ponds.

Almost 4,000 years ago, Egyptians used Almost 4,000 years ago, Egyptians used polished metal mirrors to view their polished metal mirrors to view their images.images.

Hall of Mirrors Versailles. N.d. Visiting DC. Web. 1 Mar. 2011. <http://www.visitingdc.com/paris/hall-of-mirrors- versailles.asp>.

Jean FoucaultJean Foucault

Sharp, well-defined reflected images were Sharp, well-defined reflected images were not possible until 1857, when Jean not possible until 1857, when Jean Foucault, a French scientist, developed a Foucault, a French scientist, developed a method of coating glass with silver.method of coating glass with silver.

Jean Foucault. N.d. Knowledge Rush. Web. 1 Mar. 2011. <http://www.knowledgerush.com/kr/encyclopedia/Leon_Foucault/>.

Objects and Images in Plane Objects and Images in Plane MirrorsMirrors

Plane MirrorsPlane Mirrors

A flat, smooth surface from which light is A flat, smooth surface from which light is reflected by regular reflection rather than reflected by regular reflection rather than by diffuse reflection.by diffuse reflection.

Bathroom Mirrors.Bathroom Mirrors. Regular Reflection.Regular Reflection.

Plane Mirror. N.d. EdInformatics. EdInformatics Org., n.d. Web. 1 Mar. 2011.<http://www.edinformatics.com/inventions_inventors/mirror.htm>.

ObjectsObjects

A source of spreading, or diverging light A source of spreading, or diverging light rays.rays.

Every point on an object is a source of Every point on an object is a source of diverging light rays.diverging light rays.

Anything reflected in a Anything reflected in a mirror.mirror.

Object in a Mirror. N.d. Physics Problems to Challenge Understanding. Donald Simanek, n.d. Web. 1 Mar. 2011.

<http://www.lhup.edu/~dsimanek/scenario/insight.htm>.

ImagesImages

An image is a reproduction of an image An image is a reproduction of an image formed with mirrors or lenses.formed with mirrors or lenses.

The reflected image of an object.The reflected image of an object.

Image in a Mirror. N.d. Physics 20. Physics, n.d. Web. 2 Mar. 2011. <http://www.sasked.gov.sk.ca/docs/physics/u3b22phy.html>.

Virtual ImagesVirtual Images

A reflection in a normal mirror is actually a A reflection in a normal mirror is actually a virtual image because the light rays do not virtual image because the light rays do not actually converge on that point.actually converge on that point.

Virtual Image. N.d. SMU Physics and Astronomy Demonstrations. SMU, n.d. Web. 2 Mar. 2011.

<http://www.ap.smu.ca/demos/ index.php?option=com_contentview=article&id=122&Itemid=85

Erect ImageErect Image

If the image and object are pointing in the If the image and object are pointing in the same direction as each other, it is an erect same direction as each other, it is an erect image.image.

More HelpMore Help

Mirrors Explained http://library.thinkquest.org/27356/http://library.thinkquest.org/27356/

p_mirrors.htmp_mirrors.htm http://www.pa.msu.edu/courses/2000fall/http://www.pa.msu.edu/courses/2000fall/

PHY232/lectures/lenses/images.htmlPHY232/lectures/lenses/images.html http://www.physicsclassroom.com/class/http://www.physicsclassroom.com/class/

refln/u13l4a.cfm refln/u13l4a.cfm

Concave MirrorsConcave Mirrors

Concave MirrorConcave Mirror

A concave mirror reflects light from its A concave mirror reflects light from its inner (“caved in”) surface.inner (“caved in”) surface.

Makeup mirror, Inside of a spoonMakeup mirror, Inside of a spoon

Spoon. N.d. Smooth Harold. Blake Snow, n.d. Web. 2 Mar. 2011. <http://www.smoothharold.com/smoothharolds-top-10 spoon-songs/>.

Concave MirrorConcave Mirror

Image formation by a concave mirror. N.d. Spherical Mirrors. Richard      Fitzpatrick, n.d. Web. 2 Mar. 2011. <http://farside.ph.utexas.edu/      teaching/302l/lectures/node136.html>.

Spherical Concave MirrorSpherical Concave Mirror In a spherical concave mirror, the mirror is In a spherical concave mirror, the mirror is

part of the inner surface of a hollow part of the inner surface of a hollow sphere.sphere.

Spherical aberration in a concave mirror . N.d. Spherical Mirrors. Richard      Fitzpatrick, n.d. Web. 2 Mar. 2011. <http://farside.ph.utexas.edu/      teaching/302l/lectures/node136.html>.

Principal AxisPrincipal Axis

The principal axis is the straight line The principal axis is the straight line perpendicular to the surface of a mirror at perpendicular to the surface of a mirror at its center.its center.

Focal PointFocal Point

The focal point is the point on a mirror The focal point is the point on a mirror where parallel rays meet.where parallel rays meet.

Focal point. N.d. Pirates and Revolutionaries. N.p., n.d. Web. 2 Mar. 2011.      <http://piratesandrevolutionaries.blogspot.com/2009/07/      deleuzes-dance-iii-wonders-of-phenomena.html>.

Focal LengthFocal Length

The focal length is the distance from the The focal length is the distance from the focal point to the mirror along the principal focal point to the mirror along the principal axis.axis.

Real ImageReal Image

A real image is an image that rays actually A real image is an image that rays actually converge and pass through.converge and pass through.

Can be seen on a piece of paper or Can be seen on a piece of paper or projected onto a screen.projected onto a screen.

Lens/Mirror EquationLens/Mirror Equation

You can use geometry to relate the focal You can use geometry to relate the focal length of the mirror,length of the mirror, ff, to the distance from , to the distance from the object to the mirror, the object to the mirror, ddoo,, and to theand to the distance from the image to the mirror, distance from the image to the mirror, ddii..

Lens/Mirror Equation. N.d. Online Physics Lab. PhysicsLAB, n.d. Web. 3 Mar.      2011. <http://dev.physicslab.org/      Document.aspx?doctype=3&filename=GeometricOptics_MirrorEquation.xml>.

How to Solve the EquationHow to Solve the Equation

To solve the equation:To solve the equation: Use the least common denominator, Use the least common denominator, ddiiddoo.. Take the reciprocal of both sides.Take the reciprocal of both sides.

Lens/Mirror Equation 2. N.d. Online Physics Lab. PhysicsLAB, n.d. Web. 3 Mar.      2011. <http://dev.physicslab.org/      Document.aspx?doctype=3&filename=GeometricOptics_MirrorEquation.xml>.

MagnificationMagnification

Magnification, Magnification, mm, is the ratio of the size of , is the ratio of the size of the image, the image, hhii, to the size of the object, , to the size of the object, hhoo..

m =

Magnification Equation. N.d. Physics Study Guide. N.p., n.d. Web. 3 Mar. 2011.      <http://whs.wsd.wednet.edu/Faculty/Busse/MathHomePage/busseclasses/physics/      studyguides/chapter14/Chapter14StudyGuide2010.html>.

Spherical AberrationSpherical Aberration

The image formed by parallel rays in a large The image formed by parallel rays in a large spherical mirror is a disk, not a point. This effect spherical mirror is a disk, not a point. This effect is called spherical aberration.is called spherical aberration.

A parabolic mirror has A parabolic mirror has no spherical aberration no spherical aberration because all parallel because all parallel rays are reflected to a rays are reflected to a single spot.single spot.

Spherical Aberration. N.d. Refracting vs Reflecting. N.p., n.d. Web. 3 Mar. 2011.

<http://wisp.physics.wisc.edu/astro104/lecture 7/lec7h.html>.

Convex MirrorsConvex Mirrors

Convex MirrorsConvex Mirrors

A convex mirror is a spherical mirror that A convex mirror is a spherical mirror that reflects light from its outer surface.reflects light from its outer surface.

Wide-angle mirrors for safety and security.Wide-angle mirrors for safety and security.

A Wide Angle Photo Of A Wide Angle Mirror Through A Wide Angle Mirror. N.d. Flickr. Yahoo! Inc., n.d. Web. 2 Mar. 2011.

<http://www.flickr.com/photos/2189777@N00/2764057556>.

Works CitedWorks Cited

Colwell, Catharine H., comp. "Mirror Colwell, Catharine H., comp. "Mirror Equation.“ Equation.“ Online Physics LabOnline Physics Lab. PhysicsLAB, . PhysicsLAB, n.d. Web. n.d. Web. 26 Feb. 2011. 26 Feb. 2011. <http://dev.physicslab.org/Document.as<http://dev.physicslab.org/Document.as px?px?doctype=3&filename=GeometricOptdoctype=3&filename=GeometricOptics_MirrorEquation.xml>. ics_MirrorEquation.xml>.

Kirkland, Kyle, and Sean M. Grady. "mirrors and Kirkland, Kyle, and Sean M. Grady. "mirrors and lenses in optics." lenses in optics." Science OnlineScience Online. Facts . Facts

On On File, Inc. Web. File, Inc. Web. 25 Feb. 2011. 25 Feb. 2011. <http://www.fofweb.com/activelink2.asp?Item<http://www.fofweb.com/activelink2.asp?ItemID=WE40&SID=5&iPin=STIFO0005&SingleID=WE40&SID=5&iPin=STIFO0005&SingleRecord=True>. Record=True>.

Zitzewitz, Paul W. Zitzewitz, Paul W. Physics Principles and Physics Principles and ProblemsProblems. . New York: Glencoe, 2002. Print.New York: Glencoe, 2002. Print.