The Sun (diameter = D) Subtends An Angle Of θ radians At The Pole Of A Concave Mirror Of Focal Length f. The Diameter Of The Image Of The Sun Formed By The Mirror Is: 

A transparent cube of 15 cm edge contains a small air bubble. Its apparent depth when viewed through one face is 6 cm and when viewed through the opposite face is 4 cm. Then the refractive index of the material of the cube is:   

Time taken by sunlight to pass through a window of thickness 4 mm whose refractive index is 1.5 is: 

A ray of light is incident on the surface of separation of a medium with the velocity of light at an angle 45^o and is refracted in the medium at an angle 30^o. What will be the velocity of light in the medium

A ray of light falls on a transparent glass slab with refractive index (relative to air) of 1.62. The angle of incidence for which the reflected and refracted rays are mutually perpendicular is: 

A concave mirror of focal length f produces an image n times the size of the object. If the image is real, then the distance of the object from the mirror is:    

A convex mirror of focal length f produces an image (1/n)th of the size of the object. The distance of the object from the mirror is: 

A short linear object of length L lies on the axis of a spherical mirror of focal length f at a distance u from the mirror. Its image has an axial lengthL’ equal to: 

A thin convergent glass lens (μ_g = 1.5) has a power of +5.0 D. When this lens is immersed in a liquid of refractive index  it acts as a divergent lens of focal length 100 cm. The value of μ_l must be:

A double convex lens of focal length 6 cm is made of glass of refractive index 1.5. The radius of curvature of one surface is double that of the other surface. The value of smaller radius of curvature is:

Diameter of a plano-convex lens is 6 cm and thickness at the centre is 3 mm. If the speed of light in the material of the lens is , the focal length of the lens is: