Question 1 :
To construct a ray diagram, you need a minimum of  _______ ray(s) whose path(s) after refraction through the lens are known.
Question 2 :
State whether true or false:The angle of incidence is always smaller than angle of refraction when a ray travels from air to glass, at an oblique angle
Question 3 :
Which of the following are common to images formed by both Concave and Convex lens ?
Question 4 :
The image formed by the given convex mirror when it is inside focal distance is:
Question 5 :
What is the size of image when position of object is at F, position of image is at infinity and image formed through concave mirror?<br>
Question 6 :
Which of the following is not a characteristic of the image formed by Convex lens ?
Question 7 :
The incident ray, the _______ ray and the normal lie in the same plane during refraction.
Question 8 :
The sum of the reciprocals of object distance and image distance is equal to the __________ of a mirror.<br>
Question 9 :
A plane glass plate is placed over a various coloured letters (violet, green, yellow, red). The letter which appears to raised more
Question 10 :
The power of a lens whose focal length is one metre is ______ dioptre.
Question 11 :
A person sees his virtual image by holding a mirror very close to the face. When he moves the mirror away from his face, the imagebecomes inverted. What type of mirror he is using
Question 13 :
When light goes from a denser to a rarer medium the angle of refraction is:
Question 14 :
Identify the phenomenon due to which a converging lens forms an image :
Question 16 :
How does the power of a lens change if its focal length is doubled?<br>
Question 18 :
The power of a lens is $+2.0D$. Find its focal length and state the kind of the lens.<br>
Question 19 :
A ray of light travels from air to glass at an angle of incidence of $37^{\circ}$, the angle of refraction is $24^{\circ}$. What is the refractive index of glass?<br/>(Given: $\sin 37^{\circ} = 0.60, \sin 24^{\circ} = 0.40)$
Question 20 :
The incident ray, the normal at the point of incidence and the refracted ray:
Question 21 :
Light moves from air into water. The light makes an angle of $47^{\circ}$ with the normal in the air. What angle will it make with the normal in the water?<br>The index of refraction for air is $1.00$.<br>The index of refraction for water is $1.33$
Question 22 :
A real image, equal in size to the object, is obtained when the object is placed at the centre of curvature in front of which mirror?
Question 23 :
Focal length of a lens is 50 cm. Its power would be :
Question 24 :
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 25 :
A converging lens has a focal length of $50 cm$. The power of the lens is
Question 26 :
A man is unable to see closer than 1 m clearly.The power of lenses of his spectacles should be to see nearby object.
Question 27 :
The focal length of a convex lens is $25cm$. Find its power with sign.<br/>
Question 29 :
If the magnification of a body of size 1 m is 2, what is the size of the image?
Question 30 :
Two thin lenses of focal lengths $f_{1} and f_{2}$ are in contact and coaxial. The power of the combination is :<br/>
Question 33 :
A convex mirror of focal length $f$ forms an image which is $\dfrac{1}{n}$ times the object. The distance of the object from the mirror is:
Question 35 :
The constant ratio of the sine of angle of incidence to the sine of angle of refraction is also known as:
Question 36 :
If $f$ is focal length of the lens in $cm$, then the power of a lens is equal to:
Question 37 :
The power of a lens having a focal length of $1 cm$ is :<br/>
Question 41 :
A concave mirror of focal length $f$ (in air) is immersed in water $(\mu=4/3).$ The focal length of the mirror in water will be
Question 42 :
If an object is placed $10\ cm$ infront of a concave mirror of focal length $20\ cm,$ the image will be
Question 43 :
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 44 :
State whether true or false:A concave lens forms a magnified or diminished image depending on the distance of object from it.<br/>
Question 45 :
State whether the following statement is True or False. <br/>The image formed by a convex lens is real diminished and erect.
Question 46 :
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 47 :
A lens of focal lengths $20 cm$ produces a real image of a stationary object having magnification $2$. Find the distance by which the lens should be moved so that it produces a virtual image of the same magnification.<br/>
Question 48 :
The image formed by objective lens of compound telescope will be:
Question 49 :
Magnification produced by spherical lens is $+2.5$. What is the nature of image?
Question 51 :
The image of an object formed by a convex lens when the object is placed between the lens and the focal point is -
Question 52 :
Three convex lenses are available having focal lengths of $4 cm, 40 cm$ and $4 m$ respectively. Which one could be used as magnifying glass?
Question 53 :
The glancing angle of incidence is $10^{\circ}$. What will be the glancing angle of reflection?
Question 54 :
A $4.5 cm$ needle is placed $12 cm$ away from a convex mirror of focal length $15 cm$. Find the location of the image and the magnification.
Question 55 :
The distance between an object and its doubly magnified image by a concave mirror is: [ Assume $f$ = focal length]
