What is refractive index of glass slab using travelling microscope?
The ratio R3−R1R3−R2 R 3 − R 1 R 3 − R 2 is constant and gives the refractive index of the glass slab.
What is refractive index in microscope?
Refractive Index (Index of Refraction) is a value calculated from the ratio of the speed of light in a vacuum to that in a second medium of greater density. The refractive index variable is most commonly symbolized by the letter n or n’ in descriptive text and mathematical equations.
How do you find the refractive index of glass slab?
Refractive index is also equal to the velocity of light c of a given wavelength in empty space divided by its velocity v in a substance, or n = c/v.
What is the theory of travelling microscope?
A travelling microscope is an instrument for measuring length with a resolution typically in the order of 0.01mm. It is used in laboratories to measure the refractive index of flat specimens using the geometrical concepts of ray optics (Duc de Chaulnes’ method).
What is the refractive index of glass prism?
1.5
The refractive index of glass is 1.5. The minimum angle of deviation for an equilateral prism along with the corresponding angle of incidence is desired. If the minimum angle of deviation of a prism of refractive index 1.4 equals its refracting angle, the angle of the prism is desired.
What is the refractive index of glass and air?
The refractive index of air with respect to glass is 2/3. The refractive index of diamond with respect to air is 12/5.
How is the refractive index used in glass?
Refractive index is useful for various reasons. For one thing, it can be used to calculate the focusing power of lenses and the dispersive power of prisms. It can also be used in estimating the thermophysical properties of hydrocarbons and petroleum mixtures.
What is absolute refractive index of glass?
The absolute refractive index of glass and water are 3/2 and 4/3, respectively.
What is the absolute refractive index of glass?
How to determine the refractive index of a glass slab?
To determine the refractive index of a glass slab using a travelling microscope. When a glass slab is placed on a horizontal surface, and its bottom surface is viewed from the top, due to refraction, it appears to be elevated.
How do you adjust the refractive index of a microscope?
The refractive index with respect to the medium and air is given as: To get a sufficient amount of light, place the travelling microscope (M) near the window. To make the base of the microscope horizontal, adjust the levelling screw. For clear visibility of the cross wire, adjust the position of the eyepiece.
How do you read a cross mark on a glass slab?
Place the glass slab with least thickness over the mark P. Let P 1 be the image of the cross mark. Move the microscope upwards and focus on P 1. For reading, R 2 on the vertical scale repeat step 7. Sprinkle a few particles of lycopodium powder on the surface of the slab. To focus the particle near S, raise the microscope further upward.
What is a slab in microscope?
A slab is a piece of transparent material with rectangular faces. All faces are transparent and opposite faces are parallel. The dimension along with the light travels inside the slab is called its thickness. It is a compound microscope fitted vertically on a vertical scale.