Question 1 :
Magnification is 0.5 when the object distance is 10 cm. Find the power of the concave lens :
Question 2 :
The magnification of an image by a convex lens is positive only when the project is placed:
Question 3 :
The frequency of a light wave in a material is $2\times 10^{14} Hz$ and wavelength is $5000\overset {\circ}{A}$. The refractive index of material will be :
Question 5 :
An object 20 cm from lens, has a virtual image at 10 cm from the object. The power of the lens is
Question 6 :
What is the angle of incidence when a ray of light incident on a concave mirror from its centre of curvature?
Question 7 :
The mirror which always produces an erect and virtual image of a real object is:<br/>
Question 9 :
The relation between the linear magnification $m,$ the object distance $u$ and the focal length $f$ is
Question 10 :
The power of a lens whose focal length is one metre is ______ dioptre.
Question 12 :
A converging lens has a focal length of $50 cm$. The power of the lens is
Question 13 :
When light goes from a denser to a rarer medium the angle of refraction is:
Question 14 :
A plane glass plate is placed over a various coloured letters (violet, green, yellow, red). The letter which appears to raised more
Question 15 :
If an object is placed $10\ cm$ infront of a concave mirror of focal length $20\ cm,$ the image will be
Question 16 :
$ \dfrac{\sin i}{\sin r}  =$constant, the value of constant depends upon<br/>a) Pair of media <br/>b) Color of incident light<br/>c) Wave length <br/>d) Refracting nature of material<br/>
Question 17 :
A ray of light passes through a glass slab. and the angle of emergence is found smaller than the angle of incidence. So, we may conclude that the glass slab
Question 18 :
Ratio of the size of the image to the size of the object is known as:
Question 19 :
No matter where the object is placed in front of a mirror, the image formed is virtual, erect and smaller than the object. This mirror must be: