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Q 1. If a lens has a focal length, F = +12 cm, then it is a
Concave lens
Convex lens
Diverging lens
Can be convex or concave
Q 2. What should be the position of an object kept in front of a concave mirror, in order to get a real and enlarged image?
Between the pole and the principle focus
At the principal focus
Between the principle focus and the centre of curvature
At the centre of curvature
Q 3. Power of a lens is
 1/f
 1/R
 1/u
 1/v
Q 4. Where should an object be placed in front of the convex lens so as to obtain the image formed on slide projector?
  • Between F1 and 2 F1
  • At 2 F1
  • Beyond F1
  • At F1
Q 5. A ray of light travelling in the air falls on the surface of a rectangular slab of a plastic material whose refractive index is 1.6. If the incident ray makes an angle of 53º with the normal, find the angle made by the refracted ray with the normal (sin 53º = 4/5)
20º
  •     250
30º
35º
Q 6. After reflection through a concave mirror the rays of light actually: 
Meet at a point.
Appear to meet at a point.
Never meet at a point
None of the above
Q 7. Identify the type of spherical mirror and find its radius of curvature if its focal length is - 0.5 cm 
+1 cm; Convex
-1 cm ; Concave
+1 cm; concave
-1 cm; convex
Q 8. If the absolute refractive indices of water and glass are 4/3 and 3/2 respectively, then what will be the ratio of velocity of light in water to that of glass? 
(A) 2           (B) 8/9            (C) 9/8             (D) 1/2
9/8
2
8/9
Q 9. A virtual image
can be projected on the screen.
cannot be projected on the screen.
may or may not be projected on the screen.
projected on the eyes only.
Q 10. In a convex lens, where is the image formed, when an object is placed at 2F?
At 2F on the same side
At focus (F)
Between F and 2F
At 2F on the other side
Q 11. Real image
can be projected on the screen
cannot be projected on the screen
may or may not be projected on the screen
projected on the eyes only
Q 12. Which mirror is used to concentrate the light on a given spot?
Concave mirror
Convex mirror
Plane mirror
All of the above mirrors
Q 13. A doctor has prescribed a corrective lens of power +1.5 D to one of his patients. The focal length and the nature of the lens is
 66.7 cm , converging
 - 66.7 cm , diverging
 6.67 cm , converging
 - 6.67 cm , diverging
Q 14. A spherical mirror in which silver coating is done on the inner surface is
Convex
Concave
Plano convex
Plano concave
Q 15. Which of the following device involve the use of convergence of light?
Batteries
Torches
Solar devices
Street lamps
Q 16. In which of the following devices convex mirror is used?  i. Rear view mirrors of vehicles  ii. Dentist mirror  iii. Shop security mirrors
(i) and (iii)
(i) and (ii)
(ii) and (iii)
(ii)
Q 17. Which lens always forms diminished and erect image?
Convex lens
Concave lens
Converging lens
Both convex and concave
Q 18. If the refractive index of two media are equal, then
Light will reflect in the same medium
Interface will absorb the light
No refraction will occur.
It will bend away from the normal.
Q 19. If the radius of curvature of a spherical mirror is 34.52 cm, then the focal length of that spherical mirror is
17.26 cm
-34.52 cm
69.04 cm
34.52 cm
Q 20. An object is 9 cm from a magnifying lens and its image is formed 36 cm from the lens. Magnification of the lens is.
0.25
0.5
4
0.23
Q 21. SI unit of power of lens is
Metre
Kilometre
Dioptre
Micrometre
Q 22. Which of the following is used as for shaving?
Convex
Concave
Plano convex
Plano concave
Q 23. Light always travels along a
Curved path
Circular path
Straight line path
Zigzag path
Q 24. Light changes its path as the medium changes during the transit. This is because of
   Change of wavelength
   Change of intensity
   Change of frequency
   Change of speed
Q 25. In the spherical mirrors all the distances are measured from the
Principal focus
Centre of curvature
Pole
Infinity
Q 26. Which of the following capital English letter does not show lateral inversion?
F
G
I
L
Q 27. The nature of the image formed by the convex mirror is always ________ and ________ irrespective of the position of the object.
Real and inverted
Real and erect
Virtual and erect
Virtual and inverted
Q 28. A ray of light, which is parallel to the principal axis of the concave mirror, after reflection passes through the
Centre of curvature
Principal focus of the mirror
Pole of the mirror
Focal length
Q 29. A lens which forms a virtual and enlarged image is
Convex lens
Concave lens
Diverging lens
Both convex and concave
Q 30. Where should an object be placed in front of a convex lens to get a real image of the size of the object?
At the principal focus of the lens
At twice the focal length
At infinity
Between the optical centre of the lens and its principal focus.
Q 31. What happens to the image formed by a convex lens if its lower part is blackened?
full image but of small size will be formed
Full image will form but intensity of image will be less
upper part of image will be visible
lower part of image will be visible
Q 32. The size of the image formed by the convex mirror is
Always smaller than the size of the object
Always greater than the size of the object
Same as the size of the object
Depends on the position of the object
Q 33. Which lens has a virtual focus?
Concave lens
Convex lens
Converging lens
Both convex and concave
Q 34. When the image is of the same size as the object, the magnification is
Equal to one
Greater than one
Smaller than one
Zero
Q 35. A concave lens of 20 cm focal length forms an image 15 cm from the lens. What is the object distance?
-30 cm
30 cm
-60 cm
60 cm
Q 36. Which of the following is true for reflection by spherical mirrors?
Reflection by spherical mirrors follows both the laws of reflection.
Reflection by spherical mirrors follows only the first law of reflection.
Reflection by spherical mirrors follows only the second law of reflection.
Reflection by spherical mirrors does not obey the laws of reflection.
Q 37. A person having myopic eyes uses a concave lens of focal length 50 cm. What is the power of the lens?
+ 0.02 D
- 0.02 D
+ 2 D
- 2 D
Q 38. Identify the type of spherical mirror and find its radius of curvature if its focal length is +2 cm
+4 cm; Convex
-4 cm ; Concave
+4 cm; concave
-4 cm; convex
Q 39. The mirror used as rear view mirror is
Convex
Concave
Plano convex
Plano concave
Q 40. Which of the following correctly represents the nature of an image formed by a plane mirror? 
Erect, virtual, diminished
Erect, virtual and magnified
Erect, real and diminished
Erect, virtual and of the same size

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