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When light undergoes refraction, its frequency

When light undergoes refraction, its frequency remains same.... View Article

Can absolute value of refractive index be less than unity?

Since the speed of light is maximum in vacuum, the refractive index cannot be less than unity.... View Article

Mirage is caused due to

Mirage is caused due to total Internal Reflection of light by the various layers of air. Mirage is an optical phenomenon which creates an... View Article

Total Internal Reflection is based on

Total Internal Reflection is based on reflection. Total internal reflection is based on the following two conditions: The angle of incidence... View Article

Just before setting, the sun may appear to be elliptical. This happens due to:

Refraction of light rays through the atmosphere may cause different magnifications in the mutually perpendicular directions.... View Article

A combination of two lenses with power 1D and 2D is there what is the total power

If two thin lenses of power p1 and p2 are held in contact then the power of the combination will be p = p1 +p2p = 1D + 2Dp = 3D... View Article

What is the unit of power of lens?

The unit of power of the lens is Dioptre. The power of a lens is defined as the reciprocal of the focal length. 1 dioptre is equal to the... View Article

A microscope is focused on an ink mark on the top of a table. If we place a glass slab 3cm thick on it, how should the microscope be moved to focus the ink spot again? The refractive index of glass slab is 1.5 cm.

The image of the ink spot moves up by 1cm. Refractive index = Real depth/ apparent depth1.5 = 3/ apparent depthApparent depth = 3/1.5 = 2... View Article

A convex lens has a focal length of 10cm. What is the power of the lens?

Answer: Convex lens have the ability to converge a parallel beam of light into a point. This point is called the focal point of the convex lens... View Article

A mark is made on the bottom of a vessel, over this mark a glass slab of thickness 3.5 cm and refractive index 7/4 is placed. Now water (refractive index 4/3) is poured into the vessel so that the surface of water is 8 cm above the upper surface of the slab. Looking down normally through the water, the apparent depth of the mark below the surface of water will be

Refractive index = real depth / apparent depth.Apparent depth = {8 / (4/3)} + {3.5 / (7/4)} = 6 + 2 = 8 cm... View Article

Right angled prisms can be used to

Right angled prisms can be used toa) Deviate a ray through 90 degree and 180 degree.b) Invert an image without deviation.... View Article

Which is the position of minimum deviation in prism?

When the angle of incidence is such that the refracted ray inside the prism is parallel to the base of the prism this is prism’s position of... View Article

In a concave mirror when the object is located beyond C the magnification is

In a concave mirror when the object is located beyond C the magnification is less than one as the image formed is smaller than the object.... View Article

What happens to the magnifying power of microscope, when its length increases?

The magnifying power of microscope increases, when its length is increased.... View Article

A person can see the objects lying between 25 cm and 10 m from his eye. His vision can be corrected by using lens of power:

His distance of distinct vision at 25 cm is normal. By using a concave lens of focal length 10 m he will be able to see distant objects.P =1 /f ... View Article

A slide projector gives a magnification of 10. If a slide of dimensions 3 cm x 2 cm is projected on the screen, the area of the image on the screen is:

Magnification=area of image / area of object Area of image = Magnification × area of object =10 (3 cm × 2 cm) Area of the image will be: 3 x... View Article

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