2012
NEET
MCQ
AIPMT 2012 Prelims
When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index
A.
equal to that of glass
B.
less than one
C.
greater than that of glass
D.
less than that of glass
2012
NEET
MCQ
AIPMT 2012 Prelims
A concave mirror of focal length $f$1 is placed at a distance of d from a convex lens of focal length $f$2. A beam of light coming from infinity and falling on this convex lens $-$ concave mirror combination returns to infinity. The distance d must equal
A.
${f_1} + {f_2}$
B.
$-$${f_1} + {f_2}$
C.
2${f_1} + {f_2}$
D.
$-$2${f_1} + {f_2}$
2012
NEET
MCQ
AIPMT 2012 Prelims
A ray of light is incident at an angle of incidence i, on one face of a prism of angle A (assumed to be small ) and emerges normally from the opposite face. If the refractive index of the prism is $\mu $. the angle of incidence i, is nearly equal to
A.
$\mu $A
B.
${{\mu A} \over 2}$
C.
${A \over \mu }$
D.
${A \over {2\mu }}$
2012
NEET
MCQ
AIPMT 2012 Prelims
The magnifying power of a telescope is 9. When it is adjusted for parallel rays the distance between the objective and eyepiece is 20 cm. The focal length of lenses are
A.
10 cm, 10 cm
B.
15 cm, 5 cm
C.
18 cm, 2 cm
D.
11 cm, 9 cm
2011
NEET
MCQ
AIPMT 2011 Mains
A converging beam of rays is incident on a diverging lens. Having passed through the lens the rays intersect at a point 15 cm from the lens on the opposite side. If the lens is removed the point where the rays meet will move 5 cm closer to the lens. The focal length of the lens is
A.
5 cm
B.
$-$ 10 cm
C.
20 cm
D.
$-$ 30 cm
2011
NEET
MCQ
AIPMT 2011 Mains
A thin prism of angle 15o made of glass of refractive index $\mu $1 = 1.5 is combined with another prism of glass of refractive index $\mu $2 = 1.75. The combination of the prisms produces dispersion without deviation. The angle of the second prism should be
A.
5o
B.
7o
C.
10o
D.
12o
2011
NEET
MCQ
AIPMT 2011 Prelims
A biconvex lens has a radius of curvature of magnitude 20 cm. Which one of the following options describe best the image formed of an object of height 2 cm placed 30 cm from the lens ?
A.
Virtual, upright, height = 1 cm
B.
Virtual, upright, height = 0.5 cm
C.
Real, inverted, height = 4 cm
D.
Real, inverted, height = 1 cm
2011
NEET
MCQ
AIPMT 2011 Prelims
Which of the following is not due to total internal reflection ?
A.
Working of optical fibre
B.
difference between apparent and real depth of a pond
C.
Mirage on hot summer days
D.
Brilliance of diamond
2010
NEET
MCQ
AIPMT 2010 Mains
The speed of light in media M1 and M2 are 1.5 $ \times $ 108 m/s and 2.0 $ \times $ 108 m/s respectively. A ray of light enters from medium M1 to M2 at an incidence angle i. If the rays suffers total internal reflection, the value of i is
A.
Equal to sin$-$1 $\left( {{2 \over 3}} \right)$
B.
Equal to or less than sin$-$1$\left( {{3 \over 5}} \right)$
C.
Equal to or greater than sin$-$1 $\left( {{3 \over 4}} \right)$
D.
Less than sin$-$1$\left( {{2 \over 3}} \right)$
2010
NEET
MCQ
AIPMT 2010 Mains
A rays of light is incident on a 60o prism at the minimum deviation position. The angle of refraction at the first face (i.e., incident face) of the prism is
A.
zero
B.
30o
C.
45o
D.
60o
2010
NEET
MCQ
AIPMT 2010 Prelims
A lens having focal length f and aperture of diameter d forms an image of intensity I. Aperture of diameter ${d \over 2}$ in central region of lens is covered by a black paper. Focal length of lens and intensity of image now will be respectively
A.
$f\,$ and ${I \over 4}$
B.
${{3f} \over 4}$ and ${I \over 2}$
C.
$f$ and ${{3I} \over 4}$
D.
${f \over 2}$ and ${I \over 2}$
2010
NEET
MCQ
AIPMT 2010 Prelims
A ray of light travelling in a transparent medium of refractive index $\mu $, falls on a surface separating the medium from air at an angle of incidence of 45o. For which of the following value of $\mu $ the ray can undergo total internal reflection ?
A.
$\mu $ = 1.33
B.
$\mu $ = 1.40
C.
$\mu $ = 1.50
D.
$\mu $ = 1.25
2008
NEET
MCQ
AIPMT 2008
Two thin lenses of focal lengths f1 and f2 are in contact and coaxial. The power of the combination is
A.
${{{f_1} + {f_2}} \over 2}$
B.
${{{f_1} + {f_2}} \over {{f_1}{f_2}}}$
C.
$\sqrt {{{{f_1}} \over {{f_2}}}} $
D.
$\sqrt {{{{f_2}} \over {{f_1}}}} $
2008
NEET
MCQ
AIPMT 2008
A boy is trying to start a fire by focusing sunlight on a piece of paper using an equiconvex lens of focal length 10 cm. The diameter of the sun is 1.39 $ \times $ 109 m and its mean distance from the earth is 1.5 $ \times $ 1011 m. What is the diameter of the sun's image on the paper ?
A.
6.5 $ \times $10$-$5 m
B.
12.4 $ \times $10$-$4 m
C.
9.2 $ \times $10$-$4 m
D.
6.5 $ \times $10$-$4 m
2007
NEET
MCQ
AIPMT 2007
A small coin is resting on the bottom of a beaker filled with liquid . A ray of light from the coin travels upto the surface of the liquid and moves along its surface. How fast is the light travelling in the liquid ?
A.
2.4 $ \times $ 108 m/s
B.
3.0 $ \times $ 108 m/s
C.
1.2 $ \times $ 108 m/s
D.
1.8 $ \times $ 108 m/s
2006
NEET
MCQ
AIPMT 2006
A convex lens and a concave lens, each having same focal length of 25 cm, are put in contact to form a combination of lenses. The power in diopters of the combination is
A.
zero
B.
25
C.
50
D.
infinite.
2006
NEET
MCQ
AIPMT 2006
A microscope is focussed on a mark on a piece of paper and then a slab of glass of thickness 3 cm and refractive index 1.5 is placed over the mark. How should the microscope be moved to get the mark in focus again ?
A.
2 cm upward
B.
1 cm upward
C.
4.5 cm downward
D.
1 cm downward
2004
NEET
MCQ
AIPMT 2004
The refractive index of the material of a prism is $\sqrt 2 $ and its refracting angle is 30o. One of the refracting surfaces of the prism is made a mirror inwards. A beam of monochromatic light entering the prism from the other face with retrace its path after reflection from the mirrored surface if its angle of incidence on the prism is
A.
45o
B.
60o
C.
0
D.
30o
2004
NEET
MCQ
AIPMT 2004
A beam of light composed of red and green ray is incident obliquely at a point on the face of rectangular glass slab. When coming out on the opposite parallel face, the red green ray emerge from
A.
Two points propagating in two different non parallel directions
B.
Two points propagating in two different parallel directions.
C.
One point propagating in two different directions.
D.
One point propagating in the same firections.
2003
NEET
MCQ
AIPMT 2003
An equiconvex lens is cut into two halves along (i) XOX' and (ii) YOY' as shown in the figure. Let $f,f',$ $f''$ be the focal lengths of the complete lens, of each half in case (i), and of each half in case (ii), respectively.
Choose the correct statement from the following
Choose the correct statement from the following
A.
$f' = f,f'' = 2f$
B.
$f' = 2f,f'' = f$
C.
$f' = f,f'' = f$
D.
$f' = 2f,f'' = 2f$
2003
NEET
MCQ
AIPMT 2003
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
2002
NEET
MCQ
AIPMT 2002
A bulb is located on a wall. Its image is to be obtained on a parallel wall with the help of convex lens. The lens is placed at a distance d ahead of second wall, then required focal length will be
A.
only ${d \over 4}$
B.
only ${d \over 2}$
C.
more than ${d \over 4}$ but less than ${d \over 2}$
D.
less than ${d \over 4}$
2002
NEET
MCQ
AIPMT 2002
Diameter of human eye lens is 2 mm. What will be the minimum distance between two points to resolve them, which are situated at a distance of 50 meter from eye. The wavelength of light is 5000 $\mathop A\limits^ \circ $
A.
2.32 m
B.
4.28 mm
C.
1.25 cm
D.
12.48 cm
2002
NEET
MCQ
AIPMT 2002
For the given incident ray as shown in figure, the condition of total internal refraction of this ray the required refractive index of prism will be
A.
${{\sqrt 3 + 1} \over 2}$
B.
${{\sqrt 2 + 1} \over 2}$
C.
$\sqrt {{3 \over 2}} $
D.
$\sqrt {{7 \over 6}} $
2001
NEET
MCQ
AIPMT 2001
A disc is placed on a surface of pond which has refractive index 5/3. A source of light is placed 4 m below the surface of liquid. The minimum radius of disc needed so that light is not coming out is,
A.
$\infty $
B.
3 m
C.
6 m
D.
4 m
2001
NEET
MCQ
AIPMT 2001
Optical fibre are based on
A.
total internal reflection
B.
less scattering
C.
refraction
D.
less absorption coefficient.
2000
NEET
MCQ
AIPMT 2000
A tall man of height 6 feet, want to see his full image. Then required minimum length of the mirror will be
A.
12 feet
B.
3 feet
C.
6 feet
D.
any length
2000
NEET
MCQ
AIPMT 2000
For a plano convex lens ($\mu $ = 1.5) has radius of curvature 10 cm. It is silvered on its plane surface. Find focal length after silvering
A.
10 cm
B.
20 cm
C.
15 cm
D.
25 cm
2000
NEET
MCQ
AIPMT 2000
A bubble in glass slab ($\mu $ = 1.5) when viewed from one side appears at 5 cm and 2 cm from other side, then thickness of slab is
A.
3.75 cm
B.
3 cm
C.
10.5 cm
D.
2.5 cm.
2000
NEET
MCQ
AIPMT 2000
Rainbow is formed due to
A.
scattering and refraction
B.
internal reflection and dispersion
C.
reflection only
D.
diffraction and dispersion.