MCQs on Optics :
1. Calculate the velocity of the light ray in the medium, if the critical angle for TIR from medium to the vacuum is 30°.
(A) 2 x 108 m/s
(B) 1.5 x 108 m/s
(C) 0.75 x 108 m/s
(D) 3 x 108 m/s
2. Which of the following is the combination that is used in the formation of achromatic lenses?
(A) 1 convex and 1 plane mirror
(B) 2 convex lenses
(C) 1 convex and 1 concave lens
(D) 2 concave lenses
3. How does magnifying power change for an objective lens if the focal length of the objective lens is increased?
(A) The microscope will decrease but for the telescope, it will increase
(B) The microscope will increase but for the telescope, it decreases
(C) The microscope and telescope will increase
(D) The microscope and telescope will decrease
4. Concave lenses can suffer from:
(A) Chromatic aberration but not spherical aberration.
(B) Spherical aberration but not chromatic aberration.
(C) Neither spherical nor chromatic aberration.
(D) Both spherical and chromatic aberration.
5. The radius of curvature of a convex mirror of focal length -8 centimeters is:
(A) -4 centimeters.
(B) 16 centimeters.
(C) 4 centimeters.
(D) -16 centimeters.
6. What is the magnification produced by the plane mirror?
(A) Zero
(B) +1
(C) -1
(D) Between 0 and +∞
7. The wavelength of a photon with an energy of 3.6 eV is:
(A) 869 nanomters.
(B) 345 nanometers
(C) 543 nanometers
(D) 552 nanometers.
8. The direction of propagation of an electromagnetic wave is the same as:
(A) E
(B) E.B
(C) E×B
(D) B×E
9. What happens to the refractive index on heating the liquid?
(A) Increases
(B) Decreases
(C) Remains unchanged
(D) Increases or decreases depending on the rate of heating
10. Calculate the speed of light in water if the refractive index of water is 1.33
(A) 4 x 108 m/s
(B) 2.25 x 108 m/s
(C) 1.33 x 108 m/s
(D) 3 x 108 m/s
11. What is hypermetropia?
(A) Bad vision due to age
(B) Short-sightedness
(C) Long-sightedness
(D) Formation of a layer on the eye
12. Rainbow is an example of which phenomenon?
(A) Refraction and scattering
(B) Refraction and total internal reflection
(C) Dispersion and reflection
(D) Dispersion and total internal reflection