Physics M.C.Q (1 Marks)

A point object O is placed on the principal axis of a convex lens of focal length 20 cm at a distance of 40 cm to the left of it. The diameter of the lens is 10 cm. If the eye is placed 60 cm to the right of the lens at a distance h below the principal axis, then the maximum value of h to see the image will be

If the focal length of objective and eye lens are 1.2 cm and 3 cm respectively and the object is put 1.25 cm away from the objective lens and the final image is formed at infinity. The magnifying power of the microscope is

The length of the compound microscope is 14 cm. The magnifying power for relaxed eye is 25. If the focal length of eye lens is 5 cm, then the object distance for objective lens will be

A glass prism (μ = 1.5) is dipped in water (μ = 4/3) as shown in figure. A light ray is incident normally on the surface AB. It reaches the surface BC after totally reflected, if

Magnifying power of a simple microscope is (when final image is formed at D = 25 cm from eye)

A diverging beam of light from a point source S having divergence angle a, falls symmetrically on a glass slab as shown. The angles of incidence of the two extreme rays are equal. If the thickness of the glass slab is t and the refractive index n, then the divergence angle of the emergent beam is

One face of a rectangular glass plate 6 cm thick is silvered. An object held 8 cm in front of the first face, forms an image 12 cm behind the silvered face. The refractive index of the glass is

Microscope is an optical instrument which

Light enters at an angle of incidence in a transparent rod of refractive index n. For what value of the refractive index of the material of the rod the light once entered into it will not leave it through its lateral face whatsoever be the value of angle of incidence

A ray of light falls on the surface of a spherical glass paper weight making an angle α with the normal and is refracted in the medium at an angle β. The angle of deviation of the emergent ray from the direction of the incident ray

A thin rod of length f/3 lies along the axis of a concave mirror of focal length f. One end of its magnified image touches an end of the rod. The length of the image is

The focal length of the objective lens of a compound microscope is

A point source of light B is placed at a distance L in front of the centre of a mirror of width d hung vertically on a wall. A man walks in front of the mirror along a line parallel to the mirror at a distance 2L from it as shown. The greatest distance over which he can see the image of the light source in the mirror is

In a compound microscope magnification will be large, if the focal length of the eye piece is

The focal lengths of the objective and eye-lens of a microscope are 1 cm and 5 cm respectively. If the magnifying power for the relaxed eye is 45, then the length of the tube is

A person uses spectacles of power +2D. He is suffering from

A man cannot see clearly the objects beyond a distance of 20 cm from his eyes. To see distant objects clearly he must use which kind of lenses and of what focal length

Amount of light entering into the camera depends upon

The hyper-metropia is a

Retina of eye acts like ........ of camera

Two parallel pillars are 11 km away from an observer. The minimum distance between the pillars so that they can be seen separately will be

When the object is self-luminous, the resolving power of a microscope is given by the expression

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)

The magnifying power of a microscope with an objective of 5 mm focal length is 400. The length of its tube is 20 cm. Then the focal length of the eye-piece is

An electron microscope is superior to an optical microscope in

The magnifying power of a simple microscope can be increased, if we use eye-piece of

A person is suffering from the defect astigmatism. Its main reason is

Myopia is due to

Finger prints are observed by the use of

A person wears glasses of power – 2.5 D. The defect of the eye and the far point of the person without the glasses are respectively

A man with defective eyes cannot see distinctly object at the distance more than 60 cm from his eyes. The power of the lens to be used will be

Near and far points of a human eye are

Match the List I with the List II from the combinations shown

(I)	Presbiopia	(A)	Sphero-cylindrical lens
(II)	Hypermetropia	(B)	Convex lens of proper power may be used close to the eye
(III)	Astigmatism	(C)	Concave lens of suitable focal length
(IV)	Myopia	(D)	Bifocal lens of suitable focal length

An eye specialist prescribes spectacles having a combination of convex lens of focal length 40 cm in contact with a concave lens of focal length 25 cm. The power of this lens combination in diopters is

A person wears glasses of power – 2.0 D. The defect of the eye and the far point of the person without the glasses will be

When objects at different distances are seen by the eye, which of the following remains constant

A person cannot see objects clearly beyond 2.0 m. The power of lens required to correct his vision will be

Circular part in the centre of retina is called

A person's near point is 50 cm and his far point is 3 m. Power of the lenses he requires for
(i) reading and (ii) for seeing distant stars are

For which of the following colour, the magnifying power of a microscope will be maximum

The human eye has a lens which has a

A person can see clearly only upto a distance of 25 cm. He wants to read a book placed at a distance of 50 cm. What kind of lens does he require for his spectacles and what must be its power

A short sighted person can see distinctly only those objects which lie between 10 cm and 100 cm from him. The power of the spectacle lens required to see a distant object is

In human eye the focussing is done by

A man is suffering from colour blindness for green colour. To remove this defect, he should use goggles of

The sensation of vision in the retina is carried to the brain by

A person is suffering from myopic defect. He is able to see clear objects placed at 15 cm. What type and of what focal length of lens he should use to see clearly the object placed 60 cm away

The impact of an image on the retina remains for