Optical Devices part 2

Optical Devices part 2

By Stacy King

Multiple Choice

Which of the following are examples of light

• Radio 
• Gamma
• Green
• All of the above

​Mirrors and lenses use reflection and refraction to divert light from an object and create an image.

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​Magnification

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Multiple Choice

what is the magnification equation

• M = hi over ho = - di over do
• n₁ sin θ₁ + n₂sinθ₂
• n = c over v
• I don't know :(

​Light travels in straight lines.

Mirrors are optical devices that divert light using reflection.

• ​flat mirror (also called a plane mirror)

• convex mirror (bulges out at the middle) diverge light rays

• concave mirror (bows inward at the middle) converge light rays

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​Magnification Mirrors

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Multiple Choice

A Convex mirror is a __________ device.

• Convergent
• Divergent
• Polarizing
• None of the above

Multiple Choice

A Concave mirror is a __________ device.

• Convergent
• Divergent
• Polarizing
• None of the above

These 3 mirrors each have a different magnification.

Object height is the same for each mirror, but image heights are different​

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​Magnification Mirrors

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Multiple Choice

A makeup mirror that has a magnification of 2X produces an reflected image of a pimple with a height of 1 cm what is the actual size of the pimple?

• 1/2

• 1/4

• 2

• 4

Ray Diagrams and the Law of Reflection

​Normal: an imaginary line drawn perpendicular to the reflecting surface where the light ray strikes it.

Angle of incidence: the angle between the incident ray and the normal, θi.

Angle of reflection: the angle between the reflected ray and the normal θr.

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Law of Reflection​

Multiple Choice

According to the law of reflection the angle of incidence is ____________ the angle of reflection.

• less than

• greater than

• equal to

Multiple Choice

In the diagram, which letter represents the angle of incidence?

• A

• B

• C

• D

Multiple Choice

Which is the angle of Incidence?

• A

• B

• C

• D

​A ray diagram shows the paths that light rays follow.

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Ray diagrams help explain shadow formation, and show how mirrors and lenses create images.

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Incident ray: the incoming light ray that strikes this mirror

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Reflected ray: the light ray that reflects off the surface of the mirror​

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Ray Diagrams

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Multiple Choice

A beam of light drawn as straight lines with arrows

• Incidence Ray

• Reflected Ray

• X-ray

• Ray

​The law of reflection can be used to locate images in a flat mirror.

1. Draw incident rays from the object to the mirror.

2. Draw the reflected rays using the law of reflection.

3. Extend the reflected rays until they intersect behind the mirror at the location of the image.

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Ray Diagrams

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Apparent Image Reversal

the image appears to flip right and left sides

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In reality the image is inverted front to back ​

Types of Lenses

• Concave

• Convex

Multiple Choice

this is an example of

• refraction

• diffraction

• infraction

• reflection

Multiple Choice

Why does the arrow appear to change direction as water is poured into the glass? You can try this experiment at home.

• Light waves are bouncing as they pass through air, glass and water.

• Light waves are not passing through the air, glass, and water.

• Light waves are traveling in a straight line as they pass through air, glass, and water.

• Light waves are bending as they pass through the air, glass, and water.

Concave Lens

• "caves in" on either side of lens

• thinner in the middle than at the edges

• The parallel light rays enter and then exit angled away from one another never meeting at a focal point

• Like a Convex Mirror it produces only virtual images

Multiple Choice

A Concave lens is a __________ device.

• Convergent
• Divergent
• Reflective
• None of the above

Convex Lens

• Thicker in the center than the edges

• As parallel light rays enter the lens they exit at an angle so they meet at a focal point

• If the object is between the focal point and the lens then a virtual image is produced

• If the object is beyond the focal point then a real image is produced.

Multiple Choice

Which figure represents the path light takes through a converging lens?

Multiple Choice

A convex lens is a __________ device.

• Convergent
• Divergent
• Reflective
• None of the above

Multiple Choice

A curved piece of glass that bends light toward a central focal point is called a(n)______.

• mirror

• concave lens

• convex lens

• filter

Multiple Choice

which type of lens

• opaque

• convex

• concave

• plano