Answer: True
Explanation:
The speed of light in a material medium depends on its molecular structure, in particular its electromagnetic properties, electrical and magnetic permeability. These properties may have different values for different wavelengths or frequencies of the incident light.
In this way,<u> the speed of light depends on the medium and reaches its maximum value in a vacuum</u>, so that, it will be lower in a material medium . In the vacuum (or in the air) the speed of light is 3 x 10⁸ m / s and in any other medium its value is lower.
<u>To characterize the particularities of the propagation of light in the media</u>, the refractive index is introduced
,
n = c / v
where c is <u>speed of light in a vacuum</u> and v is t<u>he speed of light in the medium</u> considered
. So the speed of light in a medium is given by the refractive index whose value is always greater than 1.
I don’t know what your talking about
Answerr
Explaination
Answer: 0.635 M
Explanation:
Molarity : It is defined as the number of moles of solute present per liter of the solution.
Formula used :

where,
n= Moles=
= volume of solution = 150 ml


as 1 mole of
gives 3 moles of
ions
Thus molarity of
= 
Molarity of
= 0.635 M
Answer:
B. Coal
Explanation: Coal is mined to produce energy.