Physics Unit 13 Light

How are rainbows formed?

Light goes into one raindrop, dispersion happens, the light reflects off the back and comes out in different colors

increase (or decrease) in size of an image produced by an optical system compared to the true size

Magnification

used to calculate the angle at which a light ray will bend as it moves from one material into another.

Snell's law

light goes from a denser medium to a less dense medium, as the angle of incidence exceeds the critical angle, the ray reflects back to the denser medium.

Total Internal Reflection.

Why does the blue shirt look blue?

absorb all the colors of visible light except for blue, reflects blue

Name examples of concave lens.

binoculars, eye glasses, cameras, flashlights

alled a converging mirror because it brings incoming parallel rays together as shown below. It causes these rays to converge

concave mirror

converging mirror , so that it is used for many purposes

concave mirror

mirror that reflects light from it's inwardly curving surface and can produce either an upright, virtual image or an inverted, real image.

concave mirror

lens that converts parallel rays of light to convergent rays and produces a real image

concave mirrors

Real images can be produced by _________ mirrors and ______ lenses.

concave, converging

curved outwards on both sides

converging lens

lens that converts parallel rays of light to convergent rays and produces a real image

converging lens

type of lens that bends light so that parallel rays entering the lens are bent toward the focal point as they exit the lens. Or... Something that bends light so that the light rays come together to a point.

converging lens

A mirror that reflects light from it's outwardly curving surface and produces an upright, reduced, virtual image.

convex mirror

eflective surface that curves outward;point where all the light that hits it appears to focus;lways forms virtual image of a real object;always produce the same kind of image

convex mirror,

angle at which light is totally reflected back into a material.

critical angle

when the incident angle is equal to the critical angle the light goes along the boundary. when the incident angle is greater than the critical angle total internal reflection takes place.

critical angle

random scattering of light rays at different angles when a beam of light is reflected off a rough surface

diffuse reflection

each color has different frequencies so slightly different speeds so each color bends a different amount. the white light turns into different colors because of this.

dispersion

variation in the amount of refraction that occurs when different wavelengths of light cross a boundary from one transparent medium to another, resulting in the breakdown of constituent wavelengths seen as spectrum. Or... The variation in refractive index with color (a rainbow is an example of dispersion in nature).

dispersion

phenomenon of splitting of a beam of white light into its seven constituent colours when passed through a transparent medium.

dispersion of ligh

lens that causes a beam of parallel rays to diverge after refraction, as from a virtual image; a lens that has a negative focal length.

diverging lens

type of lens that bends light so that parallel rays are bent away from the focal point as they exit the lens. Or... A lens that bends light so it spreads light apart instead of coming together.

diverging lens

transmitting data, voice, and images by the passage of light through thin, transparent fibres

fiber optics

use of thin, transparent fibers to transmit light; optical fibers are used in bundles to transmit information.

fiber optics

The position of the focal point with respect to the mirror along the principal axis.

focal length

The point where incident light rays that are parallel to the principal axis converge after reflecting from the mirror.

focal point

What are examples of real image?

image seen on a cinema screen (the source being the projector),

An image that is real is always _________.

inverted

angle of incidence is equal to the angle of reflection, can be used to construct the image from any object placed in front of a mirror

law of reflection

What is a converging lens?

light converges, image is real or virtual

What is a diverging lens?

light diverges, image virtual, focal points "switched"

amount that an image is enlarged or reduced in size relative to the object.

magnification

a naturally occurring optical phenomenon in which light rays are bent to produce a displaced image of distant objects or the sky.

mirage

When light travels from one medium to another does the frequency change?

no

thin rod of high-quality glass. Very little light is absorbed by the glass. Light getting in at one end undergoes repeated total internal reflection, even when the fibre is bent, and emerges at the other end.

optical fiber

flat, smooth surface from which light is reflected by regular reflection, producing a virtual image that is the same size as the object, has the same orientation, and is the same distance form the mirror as the object.

plane mirror

mirror with a flat (planar) reflective surface; flat;glass

plane mirror

A straight line perpendicular to the surface of a mirror that divides the mirror in half.

principal axis

TRANSPARENT optical element with flat, polished surfaces that refract ligh

prism

ach colour, or wavelength, making up the white light is bent, or refracted, a different amount; the shorter wavelengths (those toward the violet end of the spectrum) are bent the most, and the longer wavelengths (those toward the red end of the spectrum) are bent the least.

prism

iece of glass or other transparent material cut with precise angles and plane faces, useful for analyzing and reflecting light.

prism

object made up of a transparent material like glass or plastic that has at least two flat surfaces that form an acute angle (less than 90 degrees). White light is comprised of all the colors of the rainbow. When white light is passed through a prism, the colors of the rainbow emerge from the prism much like in the figure here (see video). We'll learn more about why a prism spreads white light out into the colors of the rainbow.

prism

optical device used to separate white light into its component colors by dispersion.

prism

diagram that shows how light rays behave as they go through an optical system.

ray diagram

an image that can be projected onto a screen.

real image

formed as a result of the intersection of the reflected light rays , It can be received on a screen , And it is always inverted .

real image

image which is located in the plane of convergence for the light rays that originate from a given object

real image

light rays actually intersect, the image can be projected using a lens;inverted optical image that is smaller than the object and is formed by the converging of light rays

real image

one that light passes through. Focus an image of the sun on a piece of paper,

real image

produced on a screen (or some other detector) when all of the rays from a single point on an object strike a single point on the screen.

real image

projected out in front of the mirror at the place where the light focuses.

real image

bending of a light wave

refraction

bending of a wave as it crosses the boundary between two media at an angle

refraction

bending of the path of a light wave as it passes from one material into another

refraction

A reflection produced by a smooth surface in which parallel light rays are reflected in parallel.

specular reflection

Reflection that occurs off smooth surfaces; the light ray is not scattered, and the reflected image is undistorted.

specular reflection

Name examples of converging lens.

telescope, binoculars, magnifying glass, camera, microscope

Occurs when light traveling from a more optically dense to a less optically dense medium approaches the boundary greater than the critical angle and reflects back.

total internal reflection

reflection of the total amount of incident light at the boundary between two media

total internal reflection

when the light is internally reflected instead of going into the next medium. this happens when the incident angle is greater than or equal to the critical angle. it must be from a higher index to a lower index.

total internal reflection

An image that is virtual is always _______.

upright

an image that cannot be projected onto a screen.

virtual image

formed as a result of the intersection of the reflected light rays extensions , It can not be received on a screen , It is always erect ( upright ) .

virtual image

image formed of diverging light rays; it is always formed on the opposite side of the mirror from the object.

virtual image

light rays don't actually intersect, our eye just perceives them to intersect. can't be projected using a lens.

virtual image

one that the light does not pass through. Simplest example: your image in a mirror.

virtual image

optical image formed when rays of light appear to be coming from a place other than where the actual object exists; a virtual image cannot be projected on a screen. Or... It is when the image is upright, it's NOT upside down

virtual image

ormed at the position where the paths of the principal rays cross when projected backward from their paths beyond the lens

virtual image

produced when rays of light reach our eyes that appear to come from a real object, but there is in fact no object at the apparent source of the light.

virtual image

appears behind the mirror. It can't be seen except by looking into the mirror.

virtual image,

When light travels from one medium to another does the speed change?

yes

When light travels from one medium to another does the wavelength change?

yes

What are examples of virtual images?

yourself in a mirror