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Physics Honors/AP 1 and 2

Chapter 23: 1-5 Assignment

Course Materials are always under revision! Weblecture content may change anytime prior to two weeks before scheduled chat session for content.

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Physics 23: 1-5 Light Rays and Reflection


Reading Preparation

Text Reading: Giancoli, Physics - Principles with Applications, Chapter 23: Sections 1 to 5

Study Points

Key Equations

Plane Mirror Reflection θ incidence   = θ reflection   θi = angle between incident ray and normal to the surface
θr = angle between reflected ray and normal to the surface
Approximate focal length of spherical mirror f   =   r 2 f = focal length (distance along primary axis between mirror and focal point
r = radius of sphere
Mirror equation 1 d 0   = 1 d i    +   1 f    1/do = distance along primary axis between object and mirror
1/di = distance along primary axis between image and mirror
Index of refraction n   =   v c n = index (varies by material in medium)
v = velocity of light in medium
c = speed of light in a vacuum
Snell's law n 1   sin   θ 1   = n 2   sin   θ 2 n1 = index of refraction in first medium
θ1 = angle of incident ray to normal to the surface
n2 = index of refraction in second medium
θ2 = angle of refracted ray in the new medium to normal at the surface

Web Lecture

Read the following weblecture before chat: The Optics of Refraction and Reflection

Study Activity

Use the simulator Ray Optics Site to play with concepts of reflection.

  • From the tools, select Mirrors > Segment and draw a vertical mirror in the middle of the screen.
  • Select a point source and place it to the left of the mirror.
  • What happens to beams that intersect with the mirror as you move the point source towards and away from the mirror?
  • What happens to beams that miss the mirror or are directed away from the mirror?
  • Select Extended Rays, which creates the path of the bent rays. Where is the focal point?
  • Use reset to clear the screen and start a new experiment.
  • Continue experimenting with mirrors of different shapes. What happens to the rays reflected from a circular curve if the source is above the axis of curvature? Closer to the mirror than the radius of curvature? Further than the focal point?

Chat Preparation Activities

Chapter Quiz

Lab Work

If you want lab credit for this course, you must complete at least 12 labs (honors course) or 18 labs (AP students). One or more lab exercises are posted for each chapter as part of the homework assignment. We will be reviewing lab work at regular intervals, so do not get behind!