Question 2 :
Lens A produces a magnification of -0.8 whereas lens B produces a magnification of +0.8. Which one of the following applies to lenses A and B?
Question 3 :
Which of the below is one of the laws of refraction?<br>
Question 5 :
The power of a lens is negative. State whether it is convex or concave?<br/>
Question 6 :
The image formed in case of a convex mirror is always ________ .
Question 8 :
Height of the image of an object on an principal axis produced by a convex lens is double the focal length of lens is $20 cm$, then image distance from the lens is:
Question 9 :
The relation among $u$, $v$ and $f$ for a mirror is:
Question 10 :
Where should the object be placed in front of a concave mirror so that the image formed is of the same size as the object?
Question 12 :
State whether true or false : A concave lens will always give a virtual, erect and diminished image.
Question 13 :
What is the nature of image formed by Concave lens ?
Question 14 :
A real, inverted and equal in size image is formed by
Question 16 :
The power of a lens whose focal length is one metre is ______ dioptre.
Question 17 :
State whether given statement is True or False<br/>A ray of light incident parallel to the principal axis of a lens, passes undeviated after refraction.<br/>
Question 18 :
A ray of light travelling in air is incident on the plane of a transparent medium. The angle of incident is $45^0$ and that of refraction is $30^0$. The refractive index of the medium with respect to air is:
Question 19 :
A ray of light passing through the .......... of the lens, passes on undeviated.
Question 21 :
The image of an object is formed by a convex lens. When that object is placed beyond the focal length is -
Question 22 :
A simple magnifying lens is used in such a way that an image is formed at $25\ cm$ away from the eye. In order to have $10$ time magnification, the focal length of the lens should be
Question 24 :
A light of wavelength $6000A^{\circ}$ in air, enters a medium with refractive index $1.5$. Inside the medium its frequency is _________ $Hz$ and its wavelength is ______ $6000 A^{\circ}$.
Question 25 :
An object is placed at a distance $2 f$ from the pole of a convex mirror of focal length $f$ . The linear magnification is:<br/>
Question 26 :
A sound wave is travelling in a medium in which the velocity is $v$. It is incident in the second medium in which the velocity of the wave is $2v$. What should be the minimum angle of incidence in the first medium, so that the wave fails to cross the surface of separation of the two media?
Question 28 :
Light ray that strikes surface of a glass slab normally. Will it deviate from its path? Yes or No<br/>
Question 30 :
State whether true or false :A transparent material bound by two surfaces, of which one or both surfaces are spherical, forms a lens.