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:

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:

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: 

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:  

A luminous point is moving at speed v₀ towards a spherical mirror, along its axis. Then the speed at which the image of this point object is moving is given by (with R = radius of curvature and u = object distance):