1. Light has a wavelength of 450 nm in a vacuum. What is its frequency? To what approximate color does this wavelength correspond?

2. What is the wavelength of light in a vacuum if its frequency is 2.3 x 10¹⁵ Hz?  To what region of the electromagnetic spectrum does this wavelength correspond?

3. Light travels with a speed of 2.8 x 10⁸ m/s in a given medium. What is the index of refraction of this medium?

4. Light has a wavelength of 550 nm in a vacuum. It then enters a medium of index of refraction 1.7.  (a) What is the frequency of this light in the vacuum?  (b) What is its frequency in the medium? (c) What is its speed in the medium? (d) What is its wavelength in the medium?  (e) What was the percent change in wavelength as the light went from the vacuum into the medium?

5. The sun is at an angle of 32^oabove the horizon. The sunlight is incident on a calm pool of water. (a) What is the angle of incidence of the sun’s light on the water’s surface?  (b) At what angle is the light refracted into the water? (c) What is the speed of the light in the water?

6. An iced-tea glass is 15 cm tall and has a diameter of 8.0 cm.  The glass sits on a garden table on a sunny day and is completely filled to the brim with water.  You are examining the glass and note that the sun is at an angle q above the horizon to the left of the glass. The sun’s light reaches the top lip of the glass, is refracted down into the water, and just barely makes it down to the water at the bottom right-hand side of the glass.  (That is, the entire bottom of the glass is just barely completely shaded by the side of the glass; the right-hand bottom edge of the glass has sunlight hitting it.)  What is the value of the angle q?

7. An in-ground pool is filled with water to a depth of 2.5 m.  The surface of the water is 35 cm below the lip of the pool’s edge.  You are standing 2.0 m from the pool’s edge. Your eyes are 1.6 m above the ground. You are looking at the bottom of the pool.  In particular, you are looking at the point that is the closest to the pool’s edge that you can see (any closer point is blocked by the edge of the pool – you would have to walk up closer to the pool’s edge to see any closer points on the pool’s bottom). How far (horizontally) from the pool’s edge is the closest point on the pool’s bottom that you can see?

8. You are looking at your image in a plane mirror mounted on the wall which is 2.3 m in front of you.  A shoe is on the floor between you and the mirror and 65 cm in front of  you. How far from you is the image of the shoe in the mirror?

9. Answer the previous question if the shoe is 1.6 m directly to your right instead of 65 cm in front of you.

10. It is common knowledge that your image in a plane mirror appears to be reversed. That is, if you are looking at your image in a plane mirror and raise your right hand, the image in the mirror raises its left hand. Thus, the mirror apparently reverses the image right-to-left.  Why then does the mirror not also reverse the image top-to-bottom? That is, why do you not also appear upside-down in the mirror as well as reversed right-to-left?  Use a ray diagram (drawing rays to and from the mirror) to help explain your reasoning.  (This is a not-uncommon question that non-science majors like to ask people who have studied optics, so be ready!)