Question 1 :
Fill in the blanks:Principal axis is also called ________ of the lens.
Question 2 :
The mirror which always produces an erect and virtual image of a real object is:<br/>
Question 3 :
Four students perform an experiment on tracing the path of a ray of light passing through a rectangular glass slab. Their individual observations are:<br>identify the incorrect observation and correct them.<br>
Question 4 :
An object 20 cm from lens, has a virtual image at 10 cm from the object. The power of the lens is
Question 5 :
The angle of incidence for a ray of light passing through the centre of curvature of a concave mirror is :
Question 7 :
The focal length of a convex mirror is $20\ cm$ its radius of curvature will be
Question 9 :
If in a plano-convex lens, the radius of curvature of the convex surface is 10 cm and the focal length of the lens is 30 cm, then the refractive index of the material of lens will be
Question 11 :
A ray of light strikes a glass plate at an angle of ${60}^{o}$. If the reflected and refracted rays are perpendicular to each other, the refractive index of glass is
Question 13 :
An object is kept at 15 cm from a convex mirror of focal length 25 cm. What is the magnification?<br/>
Question 14 :
The image of an object placed in front of a concave mirror of focal length 12 cm is formed at a point which is 10 cm more distant from the mirror than the object. The magnification of the image is:<br/>
Question 15 :
A concave mirror produces $10$ times enlarged image (real) of an object placed $1 cm$ in front of it. Where is the image located?
Question 16 :
Light ray that strikes surface of a glass slab normally. Will it deviate from its path? Yes or No<br/>
Question 17 :
The focal length of a concave mirror is f and the distance from the object to the principal focus is p. The ratio of the size of the real image to the size of the object is:<br/>
Question 18 :
You are given water, mustard oil, glycerine and kerosene. In whichof these media a ray of light incident obliquely at same angle wouldbend the most ?<br>
Question 19 :
The linear magnification for a mirror is the ratio of the size of the image to the size of the object, and is denoted by $'m'$. Then $m$ is equal to (symbols have their usual meanings)
Question 20 :
A ray of light travelling inside a rectangular glass block of refractive index $\sqrt2$ is incident on the glass-air surface at an angle o incidence of $45^o$.The refractive index of air is one. Under these conditions the ray will
Question 21 :
Aconvex lens of radii of curvature 20 cm and 30 cm respectively. It is silveredat the surface which has smaller radius of curvature. Then it will behave as $(\mu_g\, = \, 1.5)$
Question 22 :
Two thin lenses of power $+3.5D, -2D$ are placed in contact. Find the power of lens combination.
Question 23 :
A flim projector magnifies a flim of area $100 $ square centimeter on screen. If linear magnification is $4$ then area of magnified image on screen will be-
Question 24 :
The image obtained while finding the focal length of convex lens is...................
Question 25 :
A short linear object of length $b$ lies along the axis of a concave mirror of focal length $f$ at a distance u from the pole of the mirror. The size of the image is approximately equal to :<br>
