Physical Science Physics 1415 Fifth Class

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Physical Science - Physics 1415Fifth Class

• Some Final Thoughts on Reflection
• Light and Color, Investigation 3
• L3.1 - What does a lens do?
• L3.2 - How does light change direction when
  passing through a transparent material?
• L3.3 - What are some properties of a lens?
• Lab Activity - Refraction

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A Fourth Powerful Idea about Light

• Reflection of Light
• The angle that an incident light beam hits a
  reflecting surface is equal to the angle that the
  reflected beam leaves the reflecting surface.
• qi qr

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Some Final Reflection Ideas

• Handout on Reflection
• Handout on Ray Tracing
• Activities on Ray Tracing

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Investigation L3 - Refraction and Real Images

• Activity L3.1 - What does a lens do?
• 1 - Whats Your Idea?
• What is causing the reproduction on the screen?
• 2 - What are the Groups Ideas?
• 3 - Making Sense
• Is the shape of the lens important in your
  interpretation of 1 2?

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Activity L3.2 - How does light change direction
when passing through a transparent material?

• 1 - Whats Your Idea? (Predict)
• how will the beam behave if it
• enters the flat face at an angle
• as shown?
• 2 - What are your Groups Ideas?
• 3 - Making Observations
• What did you observe?
• Was it what you predicted?
• If not, how did it differ?

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Investigation L3, Activity L3.2 continued

• Consider this
• 4 - Making Sense
• What if we change the angle, what happens?
• 5 6 - how will the beam behave if it strikes
  the flat face (coming through the object) at an
  angle as shown? (Predict)

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Investigation L3, Activity L3.2 continued

• 7 - Making Observations
• What Did You Observe?
• Was it what you predicted?
• If not,how did it differ?
• 8 - Making Sense
• Do the activity and at different angles?
• Challenge activity - what about light entering a
  triangular object?
• Read the Focus on Science L3.1
• Do Homework L3.1.

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Activity L3.3 - What does a lens do?

• 1 2 - In what ways do you think the
  reproductions produced by lenses and pinholes are
  similar, and in what ways do you think they are
  different?
• 3 4 - Compare image formed by pinhole and
  lens. Are there differences in the images formed?

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Activity L3.3 - What does a lens do? - continued

• Using a lens
• 5 6 - What is your idea?
• 7 - try it!
• 8 9 - If you remove the screen, would you see
  an upside down reproduction of the object?
• 10 - try it!

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Activity L3.3 - What does a lens do? - continued

• Using a pinhole
• 11 12 - what if the lens is replaced with a
  pinhole, what would you see?
• 13 - try it!
• 14 - revise you list of similarities and
  differences between the image formed by a pinhole
  and by a lens.

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Activity L3.3 - What does a lens do? - continued

• 15 16 - How would the image be effected if
  you covered the upper half of the lens?
• 17 - try it!
• 18 - would it make a difference if you covered
  the center of the lens leaving the outer parts
  uncovered?
• Ray diagrams
• Homework L3.2 and Focus on Science L3.2

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Next Class

• Investigation 4