Question 4 :
The magnification of an image by a convex lens is positive only when the project is placed:
Question 5 :
The power of a lens having a focal length of $1\;cm$ is :
Question 7 :
Ray optics fail when the size of the obstacle is :
Question 8 :
State whether the following statement is True or False. <br/>The image formed by a convex lens is real diminished and erect.
Question 9 :
A rod is placed in a beaker of full of water. It appears to be bent inside the water. Which of the following property of light is responsible for the rod appearing to be bent?
Question 10 :
When the height of the image is less than the height of the object, then magnification will be
Question 11 :
Light moves from air into water. The light makes an angle of $47^0$ 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 12 :
In order to get a diminished virtual image, the object can be placed anywhere in front of a :
Question 14 :
An object is placed somewhere in front of concave mirror. The focal length of the mirror is $10.0 cm$. The image for this object CANNOT be formed in which of the following locations?
Question 15 :
The frequency of a light wave in a material is $2\times 10^{14} Hz$ and wavelength is $5000\overset {\circ}{A}$. The refractive index of material will be :
Question 16 :
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 18 :
The focal length of a convex mirror is $20\ cm$ its radius of curvature will be
Question 19 :
Assertion: Magnetic field lines are continuous and closed.
Reason: Magnification of a convex mirror is always positive, but that of a concave mirror may be both positive or negative.
Question 22 :
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 23 :
When the face is very close to the spoon the image formed by the outside bulged part?
Question 24 :
The maximum magnification that can be obtained with a convex lens of focal length $2.5\ cm$ is ( the least distance of distinct vision is $25\ cm$)
Question 25 :
The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should be the position of the object?
Question 26 :
The incident ray, the _______ ray and the normal lie in the same plane during refraction.
Question 29 :
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 30 :
If the power of a lens is $0.1\;D$, its focal length is
Question 31 :
When a drop of oil is spread on a water surface, it displays beautiful colours in daylight because of :
Question 32 :
A beam of light passing from air enters into the glass. Identify which of the following statements is true?<br/>
Question 33 :
Which of the following is not a use of concave lens?
Question 34 :
The distance between an object and its real image produced by a converging lens is $0.72\ m$. The magnification is $2$. What will be the magnification when the object is moved by $0.04\ m$ towards the lens?
Question 35 :
The incident ray, the normal at the point of incidence and the refracted ray:
Question 38 :
Under which of the following conditions will a convex mirror of focal length <i>f</i> produces an image ofreal object that is erect, diminished and virtual
Question 39 :
The value of the focal length of the lens is equal to the value of the image distance when the rays are
Question 40 :
Magnification is 0.5 when the object distance is 10 cm. Find the power of the concave lens :
Question 41 :
Find the power (with sign) of a concave lens of focal length $20cm$.<br/>
Question 42 :
Choose the correct answer:<br>The nature of image formed by convex mirror is:
Question 43 :
The power of a lens is negative. State whether it is convex or concave?<br/>
Question 44 :
According to laws of refraction, refraction of light at the boundary between two different regions follow:
Question 45 :
In case of a virtual and erect image, the magnification created by the mirror is
Question 47 :
The focal length of a convex lens is $25cm$. Find its power with sign.<br/>
Question 48 :
State whether true or false : A concave lens will always give a virtual, erect and diminished image.
Question 49 :
When light is refracted from a surface, which of its following physical parameters does not change?
Question 51 :
Frosted glass is widely used for translucent windows. The region where a transparent adhesive tape is stuck over the frosted glass becomes transparent. The most reasonable explanation for this is :
Question 52 :
A point object is placed on the principal axis of the convex lens of focal length 20cm at a distance 40 cm to the left on it. The diameter of the lens is 10cm. If the eye is placed 60cm to the right of the lens at a distance h below the principal axis, then max value of 'h' to see the image is
