MEDIUM
12th Uttarakhand Board
IMPORTANT
Earn 100

Obtain the formula for combined focal length of two thin lenses in contact.

Important Questions on Ray Optics and Optical Instruments

MEDIUM
12th Uttarakhand Board
IMPORTANT

What do you understand by resolving power of a microscope? How will resolving power of microscope be affected when Wavelength of light used decreases

MEDIUM
12th Uttarakhand Board
IMPORTANT

What do you understand by resolving power of a microscope? How will resolving power of microscope be affected when-

(ii) Diameter of objective lens decreases

MEDIUM
12th Uttarakhand Board
IMPORTANT
What do you understand by total internal reflection? Write essential conditions for it.
MEDIUM
12th Uttarakhand Board
IMPORTANT
A tank is filled with water to a height of 12.5 cm. The apparent depth of a needle lying at the bottom of the tank is measured by a microscope to be 9.4 cm. What is the refractive index of water?
EASY
12th Uttarakhand Board
IMPORTANT
The radii of curvature of a double convex lens are 20 cm each and refractive index of the material of the lens is 1.5. What will be focal length of the lens?
EASY
12th Uttarakhand Board
IMPORTANT
Generally Mirage is observed in deserts. Give reason for this.
MEDIUM
12th Uttarakhand Board
IMPORTANT

Draw the graph between angle of incidence (i) and angle of deviation δ for a triangular prism and show the angle of minimum deviation in it. Prove that in the condition of minimum deviation, the refractive index n of the material of triangular prism is given by following formula-

n=sinA+δm2sinA2

Where A is prism angle and δm is the angle of minimum deviation.

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