# Physics : Most materials have a refractive index of somewhere

Subject: Physics / General Physics
Question
1. Most materials have a refractive index of somewhere between 1 and 3. What is the required refractive index such that the speed of light would be lowered to v = 1.0 x 107 m/s?

a. 1.5

b. 3

c. 30

d. 10

2. Which physical phenomenon/effect best explains why there are rainbows?

a. Lucky Charms

b. Diffraction

c. Reflection

d. Refraction

3. Consider that the white space in the above picture is water such that the refractive index is 1.3. The blue block is glass so its refractive index is 1.5. If the incident angle is 30 degrees, what is the angle of reflection?

a. 30 deg

b. 60 deg

c. -30 deg

d. 90 deg

4. Using the same figure above and the information contained in question #3, which number

below is the closest to the angle of refraction?

a. 35 deg

b. 25 deg

c. 30 deg

d. 19 deg

5. If total internal reflection is happening, as in the case of fiber-optics, what is ALWAYS the

angle of refraction?

a. The same as the angle of incidence

b. Not enough information is provided to know the answer

c. 1/2 of the angle of incidence

d. 90 deg

6. The polarization of a light beam describes the…

a. direction that the light is moving.

b. direction of the electric field of the light beam.

c. direction of the magnetic field of the light beam.

d. speed of the light beam.

7. You are underwater swimming in a pool about 1 meter below the surface. Due to the refractive

index difference between the water and the air above, the life guard thinks that

a. you are 1 meter below the surface.

b. you are less than 1 meter below the surface.

c. you are more than 1 meter below the surface.

d. you are floating above the water.

8. If our sun only generated light at a red wavelength of 650 nm, we would still see the

occasional rainbow. TRUE OR FALSE

9. According to Snell’s Law, when light is incident at an angle of 0 degrees on a slab of glass,

what is the angle of refraction?

a. 30 deg.

b. 15 deg.

c. 0 deg.

d. -15 deg.

10. Which of the following is a photon with the highest amount of energy?

a. Visible red light

b. Microwave

c. Infrared