Homework Help

If a material has an index of refraction of 2.25, what is the speed of light through it?

user profile pic

lkehoe | Valedictorian

Posted April 24, 2013 at 10:53 PM via web

dislike 1 like

If a material has an index of refraction of 2.25, what is the speed of light through it?

1 Answer | Add Yours

user profile pic

mjripalda | High School Teacher | (Level 3) Educator

Posted April 25, 2013 at 12:30 AM (Answer #1)

dislike 1 like

To solve, apply the formula of index of refraction which is:

`n=c/v`

where,
n - index of refraction
c - velocity of light in a vacuum ( 3 x 10^8 m/s)  and
v - velocity of light in a medium

So, plug-in n=2.25 and c=3 x 10^8 to the formula.

`2.25=(3xx10^8)/v`

Then, multiply both sides by v.

`2.25*v=(3xx10^8)/v * v`

`2.25v=3xx10^8`

And, divide both sides by 2.25.

`(2.25v)/2.25=(3xx10^8)/2.25`

`v=1.33xx10^8`

Hence, the velocity of light in the medium is  `1.33xx10^8` m/s.

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes