Answer:
Let's start by explaining that each atom in its natural state has a specific structure of its energy levels. Where the lowest energy level is called the ground state.
At this level, as long as no energy is communicated to the atom, the electron will remain in the ground state.
What does this mean?
When an atom is in its ground state, its electrons fill the lower energy orbitals completely before they begin to occupy higher energy orbitals.
Explanation:
It is given that,
Wavelength of a beam of light in vacuum, 
(a) Let v is the speed of light in a liquid whose index of refraction at this wavelength is 1.56.
We know that,
Refractive index,

(b) The wavelength of light in material,

Let
is the wavelength of these waves in the liquid. So,

Hence, this is the required solution.
Answer:
200 , 0 , 133.33333
Explanation:
velocity = change of X / change of T
so
400/2 = 200
0/2 = 0
400/3 = 133.33333
Answer:
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