-- Looking at the dots casually, they look green because they absorb all other
colors of light, and only green light is left to proceed to your eyes. (In order for
this to work, there has to be some green in the light shining on the dots.
Daylight and most light bulbs work fine.)
-- The filter looks red because it absorbs all other colors of light, and only
the red light is left to pass through the filter and come out on the other side.
-- When the green light from the dots hits the red filter, it's absorbed in the
filter, and there's no light left to come out on the other side.
If you're looking through the filter at the dots, they look <em>black</em>.
Answer:
3 photons
Explanation:
The energy of a photon E can be calculated using this formula:

Where
corresponds to Plank constant (6.626070x10^-34Js),
is the speed of light in the vacuum (299792458m/s) and
is the wavelength of the photon(in this case 800nm).

Tranform the units

The band Gap is 4eV, divide the band gap between the energy of the photon:

Rounding to the next integrer: 3.
Three photons are the minimum to equal or exceed the band gap.
Ionic bonds are formed between a cation (metal) and an anion (nonmetal)
Answer:
Minimum thickness; t = 9.75 x 10^(-8) m
Explanation:
We are given;
Wavelength of light;λ = 585 nm = 585 x 10^(-9)m
Refractive index of benzene;n = 1.5
Now, let's calculate the wavelength of the film;
Wavelength of film;λ_film = Wavelength of light/Refractive index of benzene
Thus; λ_film = 585 x 10^(-9)/1.5
λ_film = 39 x 10^(-8) m
Now, to find the thickness, we'll use the formula;
2t = ½m(λ_film)
Where;
t is the thickness of the film
m is an integer which we will take as 1
Thus;
2t = ½ x 1 x 39 x 10^(-8)
2t = 19.5 x 10^(-8)
Divide both sides by 2 to give;
t = 9.75 x 10^(-8) m
Answer:
Part a)

Part b)


Part c)


Explanation:
Part a)
frequency of light will not change with change in medium but it will depend on the source only
so here frequency of light will remain same in both water and glass and it will be same as that in air



Part b)
As we know that the refractive index of water is given as

so the wavelength in the water medium is given as



Similarly the refractive index of glass is given as

so the wavelength in the glass medium is given as



Part c)
Speed of the wave in water is given as



Speed of the wave in glass is given as


