# Optics HW - Uplift Education

```Optics HW
Name:_____________________ Class:_______
1. When certain light rays pass from a vacuum into a block of an unknown material, the measured index of
refraction of the material is 3.50. What is the speed of light inside the block?
2. What is the frequency of light that has a wavelength in water of 600 nm if the refractive index for this light is 1.33?
3. Blue light with a wavelength of 425 nm passes from a vacuum into a glass lens; and the index of refraction is
found to be 1.65. The glass lens is replaced with a plastic lens. The index of refraction for the plastic lens is 1.54.
In which one of the two lenses does the light have the greatest speed and what is that speed?
4. A scuba diver shines a flashlight from beneath the surface of water (n = 1.33) such that the light strikes the waterair boundary with an angle of incidence of 43&deg;. At what angle is the beam refracted?
5. The travel time of signals from satellites to receiving stations on the earth varies with the frequency of the signal.
Why?
6. Two identical containers are filled with different transparent liquids. The container with liquid A appears
to have a greater depth than the container with liquid B. Which liquid has a greater index of refraction?
Explain
7. A wave passes from a lower refractive index medium to a high refractive index medium. Draw the
situation below, showing a realistic angle of refraction. Describe how the frequency, wavelength, and
speed of the wave changes in the new medium.
Drawing
Frequency –
Wavelength –
Speed -
8. Many bats are insectivores. These bats use ultrasound to locate their prey, flying insects. Would you
expect the wavelength of their ultrasound to be smaller, larger, or the same size as their prey? Explain.
9. Why can we hear noises around a corner, but not see objects around a corner?
10. In the diagram below, what is the angle of incidence? What is the angle of reflection?
11.
```