Physics > Refraction of Light > 1.0 Introduction
Refraction of Light
1.0 Introduction
2.0 Laws of refraction
3.0 Apparent shift of an object
4.0 Thin lenses
4.1 Sign convention
4.2 Some important terms
4.3 Ray tracing
4.4 Image formed by covex lens
4.5 Image formed by concave lens
5.0 Lens makers formula & Other Functions of lens.
5.1 Thin Lens Formula
5.2 Magnification and Power of lens
5.3 Combination of lenses
5.4 Displacement method to find focal length.
5.5 Silvering of lens
6.0 Total internal reflection
7.0 Refraction through prism
8.0 Scattering of light
9.0 Optical instruments
9.1 Spectrometer
9.2 Simple microscope
9.3 Compound microscope
9.4 Astronomical telescope (Refracting type)
9.5 Terrestrial telescope
9.6 Galileo's terrestrial telescope
9.7 Reflecting type telescope
1.1 Refractive index of light
4.2 Some important terms
4.3 Ray tracing
4.4 Image formed by covex lens
4.5 Image formed by concave lens
5.2 Magnification and Power of lens
5.3 Combination of lenses
5.4 Displacement method to find focal length.
5.5 Silvering of lens
9.2 Simple microscope
9.3 Compound microscope
9.4 Astronomical telescope (Refracting type)
9.5 Terrestrial telescope
9.6 Galileo's terrestrial telescope
9.7 Reflecting type telescope
Refractive index $\mu $ of a medium is defined as the ratio of the speed of light in vaccum to the speed of light in medium.
Mathematically it can be written as, $$\begin{equation} \begin{aligned} \mu = \frac{{{\text{Speed of light in vaccum}}}}{{{\text{Speed of light in medium}}}} \\ \mu = \frac{c}{v} \\\end{aligned} \end{equation} $$
So, $$\mu = \frac{c}{v}$$ or $$\mu \propto \frac{1}{v}$$
Note:
- During refraction, frequency of light ray remains constant.
- As we know, $$c = {\lambda _c}\;f$$ So, $$v = \lambda f$$ or $$\mu = \frac{{{\lambda _c}}}{\lambda }$$
where,
${\lambda _c}$: wavelength of light in vaccum
$\lambda $: wavelength of light in medium
Also, $$\mu \propto \frac{1}{\lambda }$$
