Register to reply

SI unit for refractive index

by kindaichi
Tags: index, refractive, unit
Share this thread:
kindaichi
#1
Oct19-06, 09:04 AM
P: 25
I am doing my homework and i come across a question.

What is the SI unit for refractive index?All my revision books did not have the answer.Or perhaps the book is wrong by any chance?
Phys.Org News Partner Science news on Phys.org
Experts defend operational earthquake forecasting, counter critiques
EU urged to convert TV frequencies to mobile broadband
Sierra Nevada freshwater runoff could drop 26 percent by 2100
Integral
#2
Oct19-06, 09:09 AM
Mentor
Integral's Avatar
P: 7,321
Considering that the index of refraction is defined as a ratio of velocitys, What units MUST it have? What are the units of ANYthing defined as a ratio?
kindaichi
#3
Oct19-06, 09:16 AM
P: 25
Quote Quote by Integral
Considering that the index of refraction is defined as a ratio of velocitys, What units MUST it have? What are the units of ANYthing defined as a ratio?

Hhmm..................no units?Sorry,i am a bit blur here.

zairiramli
#4
Jan19-09, 02:02 AM
P: 1
SI unit for refractive index

hi kindaichi... for you info, refractive index have no si units, since from the definition refractive index is the ratio of velocity of light in a material divided with velocity of light in vacuum. this is what is meant by "integral". as it is a ratio between velocity of light in material vs velocity of light in vacuum, both unit for the velosity was cancelled out and the only thing left is the number which indicates the ratio. and that ratio is the refractive index. but there are a lot of expression can described the refractive index. for example in brix percent. the expression is depend on the application.
Hunterbender
#5
Jan19-09, 03:05 AM
P: 54
Just adding on what's been said.

When I see these unit problem, I tend to look at the equations. For example, F = ma..even if I don't know the unit for force..I can derive it.

kg *m/s^2 is the equiv. of ma...so I know the unit for force must be kg m/s^2 (which we simplify and call it Newton, but both are correct).

Try that next time
lanca
#6
Mar29-10, 10:27 AM
P: 1
Quote Quote by Integral View Post
Considering that the index of refraction is defined as a ratio of velocitys, What units MUST it have? What are the units of ANYthing defined as a ratio?


For a RI detector, Refractive Index Range: 1 - 1.75 RIU.....what RIU mean?
dano603
#7
Apr12-12, 04:08 AM
P: 1
RIU: Refractive Units Index. It is used in optical biosensing, for evanescent wave sensors (optical waveguides, ring resonators, interferometers, surface plasmon resonance). It is the minimun detectable change in the refractive index of the surface where the evanescent wave is travelling.


Register to reply

Related Discussions
Refractive index Introductory Physics Homework 3
? Refractive Index ? Materials & Chemical Engineering 3
Refractive index Introductory Physics Homework 1
Refractive index General Physics 3
SoL and refractive index General Physics 2