1. You want to create a spotlight that will shine a bright beam of light with all of the light rays parallel to each other. You have a large concave spherical mirror and a small light bulb.
Where should you place the light bulb?
(a) At the focal point of the mirror.
(b) At the radius of curvature of the mirror.
(c) At any point, because all rays bouncing off the mirror will be parallel.
(d) None of the above; you can't make parallel rays with a concave mirror.
2. When you look at a fish in a still stream from the bank, the fish appears shallower than it really is due to refraction. From directly above, it appears
(a) Deeper than it really is.
(b) At its actual depth.
(c) Shallower than its real depth.
(d) It depends on your height above the water.