Reflection w/ curved mirrors

Parabolic and circular mirrors All horizontal light rays reflect off the surface through a single focal point Ex: satellite dishes

Concave mirrors (object outside the focus) Draw a horizontal light ray from tip of object to mirror Ray bounces back through focal point Draw a second light ray from the tip of object through the focal point to the mirror Ray bounces back horizontally The intersection of the reflected lines is where the image of the tip will form

How do you describe the image? Small Inverted Real (made with real light – you can put a screen at the image location and see an arrow)

You Try Image moves closer the mirror Image is smaller What happens to the image when the object is moved farther away from the mirror? Image moves closer the mirror Image is smaller Image is still real and inverted

What happens if you move the object between the focus and the mirror? Check – what would you see if you put a screen at the image location? Draw lines as before These reflected rays don’t intersect! Trace the path of the reflected light ray back through the mirror The intersection of these virtual rays is where the image of the tip will form

Since all the light intersects at the focal point – no image will appear (since it would be at the same place as the object itself) Object at the focal point

Draw lines as before These reflected rays don’t intersect! Trace the path of the reflected light ray back through the mirror The intersection of these virtual rays is where the image of the tip will form Convex mirrors Check – what would you see if you put a screen at the image location?

You Try Image moves away from the mirror Image is smaller What happens to the image when the object is moved farther away from the mirror? Image moves away from the mirror Image is smaller Image is still virtual and upright

Talk it out… Images are upright and small To be a concave mirror, the object would have to be between the focus and the mirror…that would be a BIG mirror All convex mirrors have small, upright, VIRTUAL images What shape is the passenger side mirror in your car? Is the image in the passenger side mirror real or virtual?

Summarize Explain why you see yourself upside down on one side of a metal spoon but right side up on the other. USE DIAGRAMS in your explanation.