ANSWERS please! I need some help!?

Question

1. How does the frequency of a beam of ultra violet light change when it goes from air into glass?

2. When light undergoes refraction, what happens to its frequency?

3. A concave mirror is placed in water. Will there be any change in focal length? Give reasons.

4. Give the ratio of velocities of light rays of wavelength 4000^A and 8000^A. (^ means degrees.)

Please answer in full detail.

Answer 1

#1: It doesn't. The frequency of a beam of light remains constant regardless of the medium through which it travels, although the wavelength may change.
#2: Absolutely nothing, for the same reason as #1.
#3: Not for a mirror. The focal length of a mirror is determined by reflection, not refraction, and the angle of reflection is equal to the angle of incidence, regardless of the medium.
#4: 1:1. The velocity of light does not depend on wavelength*

*okay, for some materials the index of refraction, and therefore the speed of light in that material, depends slightly on wavelength, which is why a prism can be used to separate light into its various colors. However, the question did not specify a particular medium, so I assumed it meant in vacuum, where the velocities of all light rays are indeed the same.

Answer 2

1.n(frequency)of any light decreases on entering in glass due to decrease in velocity.
2.decreases
3.there will be no change in its focal length.

Answer 3

I reply first, and if the answering makes me consider or makes my day, then I'll famous person. I realize...it is choosy of me, sorry. o.o But this fashion I come to be pointing my lovers and contacts to the *well stuff* you already know? ^__^ Or no less than I attempt to. But have a celeb besides only for being sufferer and knowledge. ^_^

Answer 4

this is "homework help", not "do my homework for me"