Concave & Convex Reflection

What is Concave/vex Concave refers to a surface that is indented Convex refers to a surface that is bowed out You can have both concave and convex mirrors and lenses

Working With Rays We are going to turn out the light so you can trace what concave and convex mirrors do to rays of light Follow the instructions on the sheet you are getting right now Note - You are using the ray box with 5 slits

What did you find? CONCAVECONVEX

Concave Mirrors Concave mirrors are indented mirrors that reflect light to a FOCAL point. The position of the focal point from a concave mirror is dependant on how curved the mirror is.

Concave Images If an object’s image is being reflected and the object it’s self is outside of the focal point, the image appears to be up side down & smaller If the object is between the mirror and the focal point, the image appears to be right side up and bigger An object placed right on the focal point has no image

Demonstration Time! Lets use a concave mirror and fog machine to see if the statements made on the previous slide hold true

Focal Point Distance The distance of the focal point from the concave mirror will be affected by the degree of curvature of the mirror Sharper curve = Closer focal point Gentler curve = Further focal point

Convex Mirrors Convex mirrors are bowed outward and spread light out when it is reflected Light reflected off of a convex mirror will never reach a focal point

Explain this Picture Click on hyper link

Why Smaller? The images in convex mirrors always appear to be smaller than they actually are Can you explain why?

Why… Surface Area On a flat mirror, an image is formed from light gathered directly in front of it With a convex mirror, the light that forms the image is gathered from a much larger area than the mirror its self Surface area is equal so the image stays the same size Much larger surface area so the image appears to be smaller than it really is

Obeying the Law Concave and Convex mirrors still obey the law of reflection because the angle of reflection is still equal to the angle of incidence The only difference is, because of the bend in the mirror, the angle of incidence for one ray of light will be different from the angle of incidence for the next ray of light

Obeying the Law

Your Task!!! You are being handed a simple worksheet based on the information that we covered today Use your notes along with the information found between page in your textbook to answer the questions We will be taking this up in a few classes classes from now