Quiz, Lenses Wednesday, March 4, 2015

Unit 8: EM Spectrum/Optics Wednesday, 3/4  Draw the mirrors below and label them (concave, convex) Upcoming dates:  Monday, 3/2 – EM Spectrum project due  Wednesday, 3/4 – last day to re-test on waves (revised date)  Friday, 3/6 – Open note quiz  Monday, 3/9 – Spring break starts  Thursday, 3/19 – tentative date for EM Spectrum/Optics test  Thursday, 4/2 – 5SW extra credit due by 4:30  Friday, 4/10 – End of 5SW

Warm-up answer

Quiz  Phones need to be in your bag or on my desk.  Take out your notes for the quiz.  You will have fifteen minutes to complete the quiz. When you are finished  Turn your quiz over  Find something quiet to do (no phones out) until everyone is done.

Introduction to lenses  On the back table you will find two different shaped lenses.  Place the lenses in front of the light source and observe what the light ray does.  You will trace the the incoming and outgoing (show me your rays before tracing).  Trace the rays on the paper provided (we will be adding notes to your diagrams.

Convex Lens

Concave Lens

Synthesizing what we know  For three minutes you will write about the how light rays behave (reflection and refraction) and what role the shape of lenses have on the direction of the outgoing light ray.

Ray Diagrams  Diagraming the light rays from an object allow us to predict the image we see.  Location of the image  Real or virtual  Orientation; erect or inverted  Size; enlarged, same size, reduced)  We will do this for convex lenses only!

Setting up the principal axis

Rules for Drawing Ray Diagrams Note: the point where the lines intersect is the image location. Darken in that point (point becomes the tip of the arrow)

Example 1

Example 2

Example 3

Example 4

Example 5