## Class 12 Physics MCQs Ray Optics And Optical Instruments for JEE/NEET

Here, you will get Class 12 Physics MCQ of Chapter 9 Ray Optics And Optical Instruments for cracking JEE and NEET/AIIMS. By solving these MCQs of Class 12 Physics Chapter 9 Ray Optics And Optical Instruments, you will get the confidence to crack JEE or NEET. Practice MCQ Questions for Class 12 Physics with Answers on a daily basis and score well in exams.

## Ray Optics And Optical Instruments Class 12 MCQs Questions with Answers

Which of the following cannot be polarised?
(b) transverse waves
(c) sound waves
(d) X-rays

If a mirror is approaching you at a speed of 10 ms^1, the speed with which your image approach you is
(a) 10 ms-1
(b) 5 ms-1
(c) 20 ms-1
(d) 15 ms-1

The refractive indices (R.I.) of glass and water with respect to air are 3/2 and 4/3 respectively. The R.I. of glass w.r. to w ater is
(a) 8/9
(b) 9/8
(c) 7/6
(d) 2

A convergent lens will become less convergent in
(a) oil
(b) water
(c) both of (a) and (b)
(d) none of these

A thin glass (RI = 3/2) lens has optical power of – 5D in air. Its optical power in a liquid medium with RI = 1.6 will be
(a) -2.5 D
(b) 25 D
(c) -ID
(d) 0.625 D

The angle of deviation for a prism is greatest for
(a) violet
(b) red
(c) orange
(d) yellow

A car is moving with at a constant speed of 60 km fr1 on a straight road. Looking at the rear-view mirror, the driver finds that the car following him is at a distance of 100 m and is approaching with a speed of 5 km h1. In order to keep track of the car in the rear, the driver begins to glance alternatively at the rear and side mirror of his car after every 2 s till the other car overtakes. If the the following statement (s) is/are correct?
(a ) The speed of the car in the rear is 65 km/h.
(b) In the side mirror the car in the rear would appear to approach with a speed of 5 km fr1 to the driver of the leading car.
(c) In the rear view mirror the speed of the approaching car would appear to decrease as the distance between the cars decreases.
(d) In the side mirror, the speed of the approaching car would appear to increase as the distance between the cars decreases.

Answer: (d) In the side mirror, the speed of the approaching car would appear to increase as the distance between the cars decreases.

An under-water swimmer cannot see very clearly even in absolutely clear water because of
(a) absorption of light in water
(b) scattering of light in water
(c) reduction of speed of light in water
(d) change in the focal length of eye lens

Answer: (d) change in the focal length of eye lens

A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens. Then its focal length will
(a) become zero
(b) become infinite
(c) become small, but non-zero
(d) remain unchanged

The branch of optics dealing with the formation of images using the concept of straight line propagation of light is called
(a) geometrical optics
(b) physical optics
(c) corpuscular optics
(d) quantum optics

Two lens of power -15 D and +5 D are placed in contact co-axially. The focal length of equivalent lens is
(a) -10 cm
(b) -20 cm
(c) +10 cm
(d) None

Refractive index of water and glass are 4/3 and 5/3. A light ray is going to water from glass. Then, its critical angle will be
(a) sin-14/5
(b) sin-15/6
(c) sin-11/2
(d) sin-1(2/1)

A double convex air bubble in water behaves as
(a) Convergent lens
(b) divergent lens
(c) plane slab
(d) concave mirror

In a compound microscope, image produced by objective is …………… and the image produced by eyepiece is ………..
(a) Real, real
(b) Virtual, virtual
(c) Real, virtual
(d) Virtual, real

A blue cross on the white background is illuminated with white light and is observed through red filter. What is seen?
(a) A red cross on a black background
(b) A blue cross on a red background
(c) A red cross on a blue background
(d) A black cross on a red background

Answer: (d) A black cross on a red background

When light travels from one medium to another, which of the following does not change?
(a) frequency
(b) refractive index
(c) velocity
(d) wavelength

For achromatic combination of lenses, if we use two lenses of focal length f’ and f1 dipersive power to ω and ω’ respectively, then
(a) ω = ω0, ω’= 2ω0, f’ = 2f
(b) ω = ω0, ω’ = 2ω0, f’ = -2f
(c) ω = ω0, ω’ = 2ω0, f’ = f/2
(d) ω = ω0, ω’ = 2ω0, f’ = -f/2

Answer: (d) ω = ω0, ω’ = 2ω0, f’ = -f/2

A certain far-sighted person cannot see objects closer to the eye than 100 cm. The power of the lens which will enable him to read at a distance of 25 cm will be?
(a) 3D
(b) 1D
(c) 4D
(d) 2D

A short pulse of white light is inddent from air to a glass slab at normal incidence. After travelling through the slab, the first colour to emerge is
(a) blue
(b) green
(c) violet
(d) red

Reflecting telescope utilises
(a) Convex mirror
(b) Concave mirror
(c) Plane mirror
(d) Prism

A telescope has an objective lens of 10 cm diameter and is situated at a distance of 1 km from two objects. The minimum distance between these two objects, which can be resolved by the telescope, when seen in the light of mean λ = 5000 A is of the order of
(a) 5 mm
(b) 5 cm
(c) 0.5 m
(d) 5 m

Which of-the following is not a property of light?
(a) It can travel through vacuum
(b) It has a finite speed
(c) It requires a material medium for its propagation
(d) It involve transportation energy

Answer: (c) It requires a material medium for its propagation

The RI. of the material of a prism is √2 and its refracting angle is 30°. One of the refracting surface of the prism is made a mirror. A beam of monochromatic light entering the prism from the other face retraces its path, after reflection from mirror surface. The angle of incidence on prism is
(a) 0°
(b) 30°
(c) 45°
(d) 60°

When a ray of light (white) enters a lens, undergoes a change is
(a) wavelength
(b) velocity
(c) frequency
(d) both velocity and wavelength

Answer: (d) both velocity and wavelength

The air bubble inside water shine due to
(a) Reflection
(b) Refraction
(c) T.l.R.
(d) None of these