Free Optics MCQs with Answers
665 Optics MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
Last updated
665 questions · page 21 of 34
- A. mλ = 2d/ sinθ
- B. 2λ =md sinθ
- C. mλ = 2d sinθ
- D. dλ = 2m sinθ
Explanation: nλ=2d⋅sinθ where • n is an integer determined by the order given, • λ is the wavelength of x-rays, and moving electrons, protons, and…
Correct answer: mλ = 2d sinθ- A. Green cadmium light
- B. Violet cadmium light
- C. Red cadmium light
- D. Blue cadmium light
Explanation: It is a fact.Albert A. Michelson, in 1893, measured the length of a standard meter in terms of the wavelength of red cadmium light.
Correct answer: Red cadmium light- A. 13
- B. 26
- C. 42.5
- D. 39.5
Explanation: Wavelength = λ = 450 nm = 4.5 × 10-9mNo of lines = 5000/cmOrder of image = m= 3Grating element = d = 1/5000/cm = (1/5000)cmd = (1/500000)…
Correct answer: 42.5- A. sin(30) / sin(45).
- B. sin(45) / sin(30).
- C. sin(60) / sin(45).
- D. sin(45) / sin(60).
Explanation: To calculate the refractive index of medium Q, we can use Snell's law, which relates the angles of incidence and refraction to the…
Correct answer: sin(45) / sin(30).- A. 0˚
- B. Angle of incidence
- C. Twice the angle of incidence
- D. 90˚
Explanation: Option D is correct. A 90˚ angle of refraction implies that the ray of light doesn't enter the rarer medium.
Correct answer: 90˚- A. λ = 1.23 x 10^-2 m
- B. λ = 3.25 x 10^-4 m
- C. λ = 4.55 x 10^-5 m
- D. λ = 5.1 x 10^-7 m
Explanation: In Young's Double Slit Experiment, the fringe separation (β) is given by:β=λD/xGiven:β=0.13 cm=0.0013 mx=0.05 cm=0.0005 mD=200 cm=2…
Correct answer: λ = 3.25 x 10^-4 m- A. Addition of two coherent waves to produce a stationary wave pattern.
- B. Bending and spreading of waves around an obstacle or through an opening.
- C. Change of direction when waves cross the boundary between one medium and another.
- D. Splitting of white light into its constituent colors.
Explanation: Diffraction is the spreading of waves around obstacles.
Correct answer: Bending and spreading of waves around an obstacle or through an opening.- A. 390nm
- B. 590nm
- C. 690nm
- D. 790nm
- E. 990nm
Explanation: Given:Distance between the slits (d) = 0.25 cm = 0.0025 mDistance to the screen (D) = 100 cm = 1 mDistance of the third dark fringe (y3) =…
Correct answer: 590nm- A. Magnifying power
- B. Angular magnification
- C. Simple magnification
- D. Both A and B
Explanation: The magnifying power or angular magnification is defined as the ratio of the angles subtended by the image as seen through the optical…
Correct answer: Both A and B- A. Constructive interference
- B. Destructive interference
- C. Stationary interference
- D. Simple interference
Explanation: Destructive interference at a point between the two waves takes place if the path difference between the waves at that point is equal to…
Correct answer: Destructive interference- A. reflect less
- B. diffract less
- C. reflect more
- D. diffract more
Explanation: When a light ray passes through a small opening, it undergoes a phenomenon known as diffraction.
Correct answer: diffract more- A. 1 x 10^13 Hz
- B. 1 x 10^14 Hz
- C. 1 x 10^15 Hz
- D. 1 x 10^16 Hz
Explanation: By using c = f λ f = c/λ = 3 ×10^8/3 × 10^-7 f = 1 × 10^8+7 f = 1 × 10^15 Hz Hence, option c is correct.
Correct answer: 1 x 10^15 Hz- A. Frequency
- B. Intensity
- C. Amplitude
- D. Speed
Explanation: As E = hf Where, h is constant. Energy is determined by frequency. Hence, option A is correct.
Correct answer: Frequency- A. Microwaves, Ultraviolet rays, Gamma rays
- B. Gamma rays, Ultraviolet rays, Microwaves
- C. Gamma rays, Microwaves, Ultraviolet rays
- D. Ultraviolet rays, Gamma rays, Microwaves
Explanation: •Gamma rays have the highest energy among these options. They are associated with extremely high-frequency electromagnetic waves and are…
Correct answer: Microwaves, Ultraviolet rays, Gamma rays- A. 1/2
- B. 1/4
- C. 1
- D. 2
Explanation: The correct answer is 1/2. The energy of a photon can be calculated using the formula E = hf, where E is energy, h is Planck's constant…
Correct answer: 1/2- A. Diffraction of Light
- B. An interference of light
- C. Reflection of light
- D. Polarization of light
Explanation: Diffraction is the slight bending of light as it passes around the edge of an object.
Correct answer: Diffraction of Light- A. Reflection
- B. Refraction
- C. Diffraction
- D. Interference
Explanation: This is the correct answer. Light can be polarized by reflection, especially when it reflects off a non-metallic surface at a specific…
Correct answer: Reflection- A. Converge at the principal focus
- B. Diverge from the principal focus
- C. Pass through the optical center unchanged
- D. Be refracted parallel to the principal axis
Explanation: This is the correct answer. A convex lens is a converging lens, meaning it causes parallel incident rays to converge at a point called the…
Correct answer: Converge at the principal focus- A. Compound microscope
- B. Simple microscope
- C. Transmission electron microscope
- D. Scanning electron microscope
Explanation: The Scanning Electron Microscope (SEM) produces high-resolution, three-dimensional images of surfaces by scanning a focused beam of…
Correct answer: Scanning electron microscope- A. Blue
- B. Violet
- C. Red
- D. Green
Explanation: Violet light has the highest frequency among the options provided (higher than blue, red, and green), making it the photon with the most…
Correct answer: Violet