# what is the velocity of the light in a glass with an index of refraction of 1.38

Discussion in 'Physics' started by AshokKandwal, Jan 20, 2009.

1. ### AshokKandwal Thread Starter New Member

Jan 20, 2009
3
0
what is the velocity of the light in a glass with an index of refraction of 1.38

2. ### leftyretro Active Member

Nov 25, 2008
394
5
The reciprocal of 1.38 ?

Lefty

3. ### fanta_hanu New Member

Mar 9, 2009
8
0
refractive index = 1.38(glass)

refractive index = velocity of light in vaccum/velocity of light in medium

Velocity of light in vaccum = 3810^8 met/sec
--> 1.38 = 3*(10)8 / V

--> V= 3*(10)8/ 1.38

--> V = 21.73 * (10)7 met/sec

Hope its clear now..

cheers,
Hanu

4. ### thatoneguy AAC Fanatic!

Feb 19, 2009
6,357
728
The Forum has TeX formatting with "Click and Write" functionality built in. In the editor, It is the Sigma at the left of the button bar: Ʃ

Using TeX, The above equations are much more readable, simply quote this post to see the codes used.

$
c \approx 3 \times 10^{8} \frac{m}{sec}
$

$
R_{i} = \frac {c}{V}
$

$
1.38 = \frac {3 \times 10^{8}} {V}
$

$
V \approx \frac {3\times 10^{8}}{1.38}
$

$
V \approx 21.73\times 10^{7}\frac {m}{sec}
$