Physics questions... Please help.?

Question

Hi, here are the questions I have, and I have no idea on how to answer them, any help would be greatly appreciated, thanks!

1.a YAG laser has a frequency of 2.8E14, what is its wavelenght?
2. What is the frequency of light that has a wavelength of 480nm
3. an object is located 1.8m from a plane mirror, how far is the image away from the object
4. what is the critical angle for dimond submerged in water?
5. what is the index of refraction of an object in wich light travells at 1.97e6

Thanks, the ansers to these questions would be really appreciated.

Answer 1

The relationship between frequency f, wavelength λ, and velocity c for light is

f λ = c

Use that to solve (1) and (2).

The image distance for a plane mirror is equal to the object distance.

The index of refraction of diamond is about 2.42 and that of water is about 1.33. The critical angle is computed as

arc-sin ( 1.33 / 2.42 )

Index of refraction is the ratio of the speed of light within a medium, v, to the speed of light in a vacuum, c:

n = v / c

Plug in v and c and solve for n.