Question 1 :
The power of a lens whose focal length is one metre is ______ dioptre.
Question 2 :
A wave has velocity v in medium P and velocity 2v in medium Q. If the wave is incident in medium P at an angle of 30, then the angle of refraction will be
Question 3 :
If the power of a lens is $0.1\;D$, its focal length is
Question 4 :
<br>Which is the human organ which behaves like an optical instrument having lens and a screen?
Question 5 :
Which of the following is not a characteristic of image formed by a Concave lens ?
Question 7 :
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 8 :
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 9 :
A student obtained a sharp inverted image of a distant tree on a screen placed in front of the concave mirror. He then removed the screen and tried to look into the mirror. He would now see:
Question 10 :
A thin convex lens of focal length $10\ cm$ is placed in contact with a concave lens of same material and of same focal length. he focal length of combination will be
Question 11 :
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 12 :
State whether the following statement is True or False. <br/>A real image can be obtained by putting an object at any distance from a convex mirror
Question 13 :
If the focal length of a lens is $50\;cm$, its power would be
Question 14 :
Identify the phenomenon due to which a converging lens forms an image :
Question 15 :
The angle of incidence for a ray of light passing through the centre of curvature of a concave mirror is :
Question 16 :
The mirror which always produces an erect and virtual image of a real object is:<br/>
Question 17 :
To observe the hydra bud clearly. Raju should see it first under the low power lens and then under the high power lens in order to see 
Question 19 :
Due to refraction, when seen from outside,a coin placed under water in a bowl, appears to
Question 20 :
On the basis of their experiment, "To trace the path of a ray of light through a rectangular glass slab," students of a class arrived at which one of the following conclusions :
