Geometrical Optics

Diameter of a plano-convex lens is \(6\) \(cm\) and thickness at the center is \(3mm\). If speed of light in material of lens is \(2 \times {10^8}\,m/s,\) the focal length of the lens is

The graph between angle of deviation \(\left( \delta \right)\) and angle of incidence \((i)\) for a triangular prism is represented by

An object \(2.4\) \(m\) in front of a lens forms a sharp image on a film \(12\) \(cm\) behind the lens. A glass plate \(1\) \(cm\) thick, of refractive index \(1.50\) is interposed between lens and film with its plane faces parallel to fil...

Let \(x\)-\(z\) plane be the boundary between two transparent media. Medium \(1\) in \(z \ge 0\) has a refractive index of \(\sqrt 2\) and medium \(2\) with \(z < 0\) has a refractive index of \(\sqrt 3 .\) A ray of light in medium \(1\)...

A car is fitted with a convex side-view mirror of focal length \(20\) \(cm\). A second car \(2.8m\) behind the first car is overtaking the first car at a relative speed of \(15\) \(m/s\). The speed of the image of the second car as seen in ...

An initially parallel cylindrical beam travels in a medium of refractive index \(\mu \left( I \right) = {\mu _0} + {\mu _2}\,I,\) where \({\mu _0}\) and \({\mu _2}\) are positive constants and \(I\) is the intensity of the light beam. The i...

An initially parallel cylindrical beam travels in a medium of refractive index \(\mu \left( I \right) = {\mu _0} + {\mu _2}\,I,\) where \({\mu _0}\) and \({\mu _2}\) are positive constants and \(I\) is the intensity of the light beam. The i...

In an optics experiment, with the position of the object fixed, a student varies the position of a convex lens and for each position, the screen is adjusted to get a clear image of the object. A graph between the object distance \(u\) and t...

A transparent solid cylindrical rod has a refractive index of \({2 \over {\sqrt 3 }}.\) It is surrounded by air. A light ray is incident at the mid-point of one end of the rod as shown in the figure.

The incident angle \(\theta\) for whi...

A student measures the focal length of a convex lens by putting an object pin at a distance \('u'\) from the lens and measuring the distance \('v'\) of the image pin. The graph between \('u'\) and \('v'\) plotted by the student should look ...

Two lenses of power \(-15\) \(D\) and \(+5\) \(D\) are in contact with each other. The focal length of the combination is

The refractive index of a glass is \(1.520\) for red light and \(1.525\) for blue light. Let \({D_1}\) and \({D_2}\) be angles of minimum deviation for red and blue light respectively in a prism of this glass. Then,

A fish looking up through the water sees the outside world contained in a circular horizon. If the refractive index of water is \({4 \over 3}\) and the fish is \(12\) \(cm\) below the surface, the radius of this circle in \(cm\) is

A thin glass (refractive index \(1.5\)) lens has optical power of \(-5\) \(D\) in air. Its optical power in a liquid medium with refractive index \(1.6\) will be

A plano convex lens of refractive index \(1.5\) and radius of curvature \(30\) \(cm\). Is silvered at the curved surface. Now this lens has been used to form the image of an object. At what distance from this lens an object be placed in ord...

A light ray is incident perpendicularly to one face of a \({90^ \circ }\) prism and is totally internally reflected at the glass-air interface. If the angle of reflection is \({45^ \circ }\), we conclude that the refractive index \(n\)

The image formed by an objective of a compound microscope is

To get three images of a single object, one should have two plane mirrors at an angle of

An astronomical telescope has a large aperture to

Wavelength of light used in an optical instrument are \({\lambda _1} = 4000\mathop A\limits^ \circ\) and \({\lambda _2} = 5000\mathop A\limits^ \circ ,\) then ratio of their respective resolving powers (corresponding to $${\lambda _1}...

Which of the following is used in optical fibres?

If two mirrors are kept at \({60^ \circ }\) to each other, then the number of images formed by them is