Advertisements
Advertisements
प्रश्न
What type of wavefront will emerge from a (i) point source, and (ii) distance light source?
Advertisements
उत्तर
(i) For point source, wavefront will be spherical.
(ii) For a distannt light source, the wavefronts will be plane wavefronts.
APPEARS IN
संबंधित प्रश्न
The equation of refraction at a spherical surface is \[\frac{\mu_2}{\nu} - \frac{\mu_1}{\mu} = \frac{\mu_2 - \mu_1}{R}\]
Taking \[R = \infty\] show that this equation leads to the equation
\[\frac{\text{ Real depth }}{\text{ Apparent depth }} = \frac{\mu_2}{\mu_1}\]
for refraction at a plane surface.
A converging lens of focal length 15 cm and a converging mirror of focal length 10 cm are placed 50 cm apart with common principal axis. A point source is placed in between the lens and the mirror at a distance of 40 cm from the lens. Find the locations of the two images formed.
A converging lens of focal length 15 cm and a converging mirror of focal length 10 cm are placed 50 cm apart. If a pin of length 2.0 cm is placed 30 cm from the lens farther away from the mirror, where will the final image form and what will be the size of the final image?
Two convex lenses, each of focal length 10 cm, are placed at a separation of 15 cm with their principal axes coinciding. (a) Show that a light beam coming parallel to the principal axis diverges as it comes out of the lens system. (b) Find the location of the virtual image formed by the lens system of an object placed far away. (c) Find the focal length of the equivalent lens. (Note that the sign of the focal length is positive although the lens system actually diverges a parallel beam incident on it.)
Use the above relation to obtain the condition on the position of the object and the radius of curvature in terms of n1and n2 when the real image is formed.
Define the term ‘focal length of a mirror’.
Region I and II are separated by a spherical surface of a radius of 25 cm. An object is kept in the region I at a distance of 40 cm from the surface. The distance of the image from the surface is ______.
A spherical surface of radius R separates two medium of refractive indices µ1 and µ2, as shown in figure. Where should an object be placed in the medium 1 so that a real image is formed in medium 2 at the same distance?

A point object in the air is placed symmetrically at a distance of 60 cm in front of a concave spherical surface with a refractive index of 1.5. If the radius of curvature of the surface is 20 cm, find the position of the image formed.
Assertion: If critical angle of glass-air pair `("μg" = 3/2)` is θ1 and that of water-air pair `("μw" = 4/3)` is θ2, then the critical angle for the water-glass pair will lie between θ1 and θ2.
Reason: A medium is optically denser if its refractive index is greater.
