Question 1 :
A photograph of a horse is taken by a camera whose lens has been painted with black stripes. The photograph will be of a :
Question 3 :
According to laws of refraction, refraction of light at the boundary between two different regions follow:
Question 5 :
The radius curvature for a convex lens is $$40\ cm$$, for each surface. Its refractive index is $$1.5$$. The local length will be
Question 6 :
Identify the phenomenon due to which a converging lens forms an image :
Question 10 :
A converging lens has a focal length of $$50 cm$$. The power of the lens is
Question 12 :
Find the power (with sign) of a concave lens of focal length $$20cm$$.<br/>
Question 13 :
If the focal length of a lens is $$50\;cm$$, its power would be
Question 14 :
A short sighted person can see distinctly only those objects which lie between $$10cm$$ and $$100cm$$ from him, The power of the spectacle lens required to see a distance object is
Question 15 :
A ray of light incident at a point on the principal axis of a convex lens passes undeviated through the lens. What special name is given to this point on the principal axis?<br>
Question 16 :
Two thin lenses of focal lengths $$f_{1} and f_{2}$$ are in contact and coaxial. The power of the combination is :<br/>
Question 17 :
A ray of light strikes the glass slab at an angle of $$50^o$$. Then the angle of incidence will be _____.
Question 18 :
A ray passing with which part of a lens emerges undeviated ?
Question 19 :
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 :
Question 21 :
State whether true or false.<br/>The images formed by a convex mirror are always erect and enlarged.
Question 22 :
In case of a virtual and erect image, the magnification created by the mirror is
Question 24 :
When a ray of light passes through a rectangular slab, made up of some transparent material other than glass, the emergent ray is
Question 25 :
Which of the following is not an application of convex lens?
Question 26 :
The mirror which always produces an erect and virtual image of a real object is:<br/>
Question 27 :
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 28 :
The relation between the linear magnification $$m,$$ the object distance $$u$$ and the focal length $$f$$ is
Question 29 :
When the height of the image is less than the height of the object, then magnification will be
Question 30 :
When the face is very close to the spoon the image formed by the outside bulged part?
Question 31 :
When a ray of light passes from an optically less dense medium to a more dense medium, it :
Question 32 :
A ray of light incident at the optical centre of lens, passes undeviated after refraction.<br>
Question 33 :
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 34 :
Which of the following term is not associated with a lens?
Question 35 :
<br>Which is the human organ which behaves like an optical instrument having lens and a screen?
Question 36 :
Due to refraction, sunrise appears ______ sun comes to horizon and sunset appears______sun leaves horizon respectively.
Question 37 :
The angle of incidence for a ray of light passing through the centre of curvature of a concave mirror is :
Question 38 :
What is the power of the lens, if the far point of a short sighted eye is $$200\ cm$$?
Question 42 :
An object 20 cm from lens, has a virtual image at 10 cm from the object. The power of the lens is
Question 43 :
A convex lens makes a real image $$4\ cm$$ long on a screen. When the lens is shifted to a new position without disturbing the object, we again get a real image on the screen which is $$16\ cm$$ tall. The length of the object must be
Question 44 :
"Value of refractive index remains same for light rays with different wavelength and for a particular material"
Question 45 :
The power of a lens is $$+2.0D$$. Find its focal length and state the kind of the lens.<br>
Question 47 :
Which of the following is not a characteristic of image formed by Concave lens ?
Question 48 :
No matter how far you stand from a mirror, your image appears erect. The mirror is likely to be<br>
Question 49 :
Choose the correct answer:<br>The nature of image formed by convex mirror is:
Question 50 :
Material $$1$$ has an index of refraction of $$1.15$$.<br/>Material $$2$$ has an index of refraction of $$2.30$$.<br/>If light passes from air into each of these materials at the same angle of incidence, how will the angle of refraction in material $$1$$ compare to the angle of refraction in material $$2$$?
