Mr' Loths

1
Lenses

• Mr. Loths
• 7th Grade Science
• Created by Mr. Whittaker

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Convex Lenses

• Convex a lens that is thicker in the middle
  than at its ends.
• Ex. eyeglasses (farsighted, bifocals), camera,
  magnifying glass, telescope

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Concave Lenses

• Concave a lens that is thicker at the ends than
  it is in the middle.
• Ex. eyeglasses (nearsighted)

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Match the ITEMS with their LENSES.
Convex Lenses
Concave Lenses
BOTH
There are very few thing that use a concave
lenses !!
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How do lenses help us see?

• Correct
• Farsightedness
• Nearsightedness

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Plane Mirrors

• Plane Focus point (virtual image) is formed
  behind mirror. Image is the same size.

Can you name some a plane mirrors?
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Concave Mirrors

• Concave focal point forms in front of
• mirror.

Click to see a diagram
Can you name some things that use a concave
mirror?
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Convex Mirrors

• Convex smaller virtual image right side up.
• closer than appears
• used also in driveways and store security.

Driveway mirror
Side view mirror
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Reflection vs. Refraction
The bouncing of light waves off a surface

• Reflection ?

The bending of light waves as they pass
Refraction ?