Wave Optics

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thanks Ganu.. but i found a better version... chk this out..

Spectrometer

An optical instrument, which is used for observing pure spectra of sources of light in the laboratory.
Main parts of the spectrometer are:
1) Collimator 2) Prism table 3) Telescope

Description

The collimator renders a parallel beam of light through the two coaxial cylindrical tubes. One end of the collimator has a slit through which light enters the tube and falls on lens L situated at the other end.
Prism table is a circular plate fixed over a vertical stand of adjustable height. The free end of stand consists of a circular scale graduated in degrees from 0^o to 360^o along with verniers to enable to read the position of the prism.
Telescope is meant for observing the spectrum and is mounted horizontally on a vertical stand attached to the circular scale. The telescope can be rotated about the prism table.

Adjustments
The telescope is turned towards a distant object and is focused to see a clear image of object. It is then brought in line with the collimator. A clear image of the slit is obtained by adjusting the screws in the collimator. The prism is kept over the prism table.

Determination of m Material of a Prism
The prism is placed over the table such that parallel rays from collimator falls on the sides AB and AC. Move the telescope in the position T₁ to catch the brightest image of the slit formed by reflection of light at faces AB and AC. The cross wire is made to coincide with image and reading on the circular scale is noted. The telescope is turned to position T₂ and the same procedure is repeated. If q is the difference between the two readings through which the telescope is turned then
Wave Optics - Page 2 Img225

Determination of angle of prism

Determination of Angle of Minimum Deviation
To determine the angle of minimum deviation the side AB of the prism is made to face the ray of light. On looking through the face AC and rotating the prism table, the image of slit also turns. For a particular position of the prism, the slit becomes stationary. On further rotating the prism table, image of slit turns in the opposite direction. Fix the prism when the image of the slit is stationary. This is the position of minimum deviation. Coincide the cross wires of the telescope in this position and note the reading. Remove the prism and catch the direct ray and once again note the reading. The difference between the two readings gives the angle of minimum position.

Knowing dm and A, the refractive index (m) of the material of the prism can be calculated using the prism formula
$Wave Optics - Page 2 Refractive-index-prism-formula$

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How can we easily remember electromagentic spectrum wavelengths and frequencies? is there any way other than cramming it..?

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Raul's Mother Is Visiting Uncle Xavier's Garden......

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thanks...this is much better.....

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How r u remembering the wavelengths and frequencies?

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i d0nt have any exclusive method...sorry WinRule...i have the picture of the spectrum stuck on the ceiling right above my bed...including many other things...and so by looking at it constantly before sleeping..i kn0w it... Twisted Evil

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great..!

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