A “Visual” Review Fuss Physical Science

How do you locate the image in a Curved Mirror Situation. Pick a point on the object (usually the one furthest from the principal axis), and then draw 2 intersecting rays that obey the following rules: Any ray parallel to the principal axis is reflected through the focus. 2. Any ray through the focus is reflected parallel to the principal axis. Any ray through the center of curvature is reflected back along the incident ray (back along itself)

Concave/Converging Mirrors “OUTSIDE“ the focus C F Moving towards the focus, the image is REAL, inverted. It could be smaller, the same size, or larger than the image (depending on the object location)

Concave/Converging Mirrors “ON” the focus C F NO IMAGE !!!!!! The lines never cross!!!!

Concave/Converging Mirrors C F “INSIDE” the focus Moving towards the mirror, the image is VIRTUAL, UPRIGHT, and gets smaller (although the image is ALWAYS larger than the object itself).

Convex/Diverging Mirrors Note: All rays want to pass through F, but none do F C C’ F’ When an object gets closer to the mirror, its image is VIRTUAL, UPRIGHT, and keeps getting smaller (and the images are always smaller than the object).

Concave mirrors Convex mirrors Can make small objects appear larger Make-up mirrors, shaving mirrors Convex mirrors Can make large objects appear smaller (see a WIDE view) Security mirrors, Driveway mirrors, Car door mirrors

LENSES Fuss Physical Science

How do you locate the image formed in a LENSE Situation. Any ray parallel to the principal axis is reflected through the focus. 2. Any ray through the focus is reflected parallel to the principal axis. 3. Any ray through the center of the lens passes directly through the lense following its same path.

Image Formation in CONVERGING Lenses

Image Formation in Diverging Lenses

Cameras …… ….. and the human eye NOT ON TEST, BUT ON FINAL EXAM!!!! BOTH use converging lenses with the object far beyond the focus and both form INVERTED images. Film ….. and the human eye

Magnifying Glasses 2F’ F’ F 2F Larger, virtual image that you see Object that you are looking at (under the lens)

Film Projectors White screen

Muscles that “tense” the lens Cornea: Protective “Window” of eye Iris: Colored part that acts like a camera shutter. Pupil: Hole in the middle of the iris. Lens: has adjustable focal length. Retina: Where image is formed. Optic nerve: Sends image to brain where it is flipped upside down. The Human Eye Muscles that “tense” the lens

Furthest Point that the eye can see clearly Far Point Furthest Point that the eye can see clearly Diverging Lens makes the light rays cross further away (on the retina) allowing you to see a clear image. Object beyond the far point can’t be focused clearly on the retina b/c lines cross too soon

Closest Point that the eye can see clearly Far-Sightedness Converging Lens makes the light rays cross sooner, allowing a clear image to form on the retina Focus of lens Near Point Object inside the near point can’t be focused clearly on the retina b/c light rays cross too late Closest Point that the eye can see clearly