A goldfish is swimming at 2.00 cm/s toward the front wall of a rectangular aquarium. What is the apparent speed of the fish measured by an observer looking in from outside the front wall of the tank?

Jennifer stretches in front of the 2.0 m tall mirror in her hallway, aiming the green laser pointer at the angle 45 degrees below the horizontal and observes the reflection on the floor, distance x away. If the laser is initially 1.56 m above the ground and Jennifer is standing 1.56 m away from the mirror, how far away from the mirror is the spot on the floor? [note that x doesn't need to be smaller than d, it just happens to be in this sketch]| h d. x 2.0 m

Walking along the edge of a pool, you see a quarter resting on the bottom of the pool. The light reflecting off the quarter enters your eyes at a 37o angle below the horizontal. Is the quarter closer or farther away from you than it appears?

In order to identify an unknown material you are asked to solve for the critical angle of the material. In order to test this you set up a beam of light that strikes the unknown substance from air (n = 1.0) at an angle of 30° with respect to the normal.  It continues on in the substance at an angle of 23° with respect to the normal.  What is the critical angle for the unknown substance?     51°     55°     60°     63°