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 2 of 34
- A. 1 over f equals 1 over v plus 1 over u, with a sign convention applied
- B. f equals u plus v
- C. f equals uv
- D. 1 over f equals u plus v
Explanation: The lens formula relates the reciprocals rather than the quantities themselves, and a consistent sign convention is essential, with real…
Correct answer: 1 over f equals 1 over v plus 1 over u, with a sign convention applied- A. Nature of light waves
- B. Properties of light
- C. Characteristics of sound
- D. Lenses and mirrors
Explanation: Optics studies light, including its nature, properties, lenses and mirrors; characteristics of sound belong to acoustics.
Correct answer: Characteristics of sound- A. 1 meter
- B. 2 meter
- C. ½ meter
- D. ¼ meter
Explanation: Lens power is P = 1/f, with P in dioptres and focal length f in metres.
Correct answer: 1 meter- A. 8500 - 9800 angstrom
- B. 7800 - 8000 angstrom
- C. 3900 - 7600 angstrom
- D. 1300 - 3000 angstrom
Explanation: Visible light has wavelengths of approximately 3900 to 7600 Å, or 390 to 760 nm.
Correct answer: 3900 - 7600 angstrom- A. Dichromatic
- B. Monochromatic
- C. Pentachromatic
- D. None of these
Explanation: A laser source is commonly used in optical-fibre communication because its nearly single-wavelength light suffers less spreading and…
Correct answer: Monochromatic- A. line
- B. bottom
- C. point
- D. vertex
Explanation: A point is an ideal geometrical object representing position only, with no length, width or thickness.
Correct answer: point- A. behind the retina
- B. in front of the retina
- C. on the retina
- D. on the blind spot
Explanation: Concave lenses diverge incoming rays and are used to correct myopia, in which the eye focuses distant objects before they reach the…
Correct answer: in front of the retina- A. reflection of light
- B. refraction of light
- C. Refraction and total internal reflection of light
- D. Scattering of light
Explanation: A mirage forms when light travels through air layers at different temperatures and densities, causing refraction, often followed by total…
Correct answer: Refraction and total internal reflection of light- A. 0
- B. 1
- C. 2
- D. Infinite
Explanation: At every point on a circle there is one tangent, and a circle contains infinitely many points.
Correct answer: Infinite- A. Vaccum
- B. Glass
- C. Water
- D. Air
Explanation: The speed of light in a medium is v = c/n, so it is least in the medium with the greatest refractive index.
Correct answer: Glass- A. Vernier Callipers
- B. Screw Gauge
- C. Bore Gauge
- D. None
Explanation: The inside jaws of vernier callipers are designed to measure internal diameters, so they can measure the inner diameter of a test tube.
Correct answer: Vernier Callipers- A. Candela
- B. Cm
- C. Ampere
- D. Second
Explanation: Candela is the SI base unit of luminous intensity, and its symbol is cd.
Correct answer: Candela- A. Further stimulation
- B. Lasing more
- C. For producing more energetic lasers
- D. AllIndustrial Materials & Equipment
Explanation: The mirrors in a laser cavity reflect photons back through the active medium, causing repeated stimulated emission and maintaining the…
Correct answer: Further stimulation- A. Ne only
- B. He-Ne both
- C. Electrons of He
- D. Electrons Ne
Explanation: In a helium-neon laser, excited helium atoms transfer energy to neon atoms, but the actual laser transitions and emitted photons come from…
Correct answer: Ne only- A. The ions in a crystal are well arranged
- B. The lines in a diffraction grating cannot reflect X-rays.
- C. The penetration power of X-rays is high in a diffraction grating
- D. The wavelengths of X-rays are of the same order of magnitude as the separation between atoms in a crystal
Explanation: X-rays have wavelengths of about 10^-10 m, comparable to the spacing between atoms in a crystal, so the crystal produces Bragg…
Correct answer: The wavelengths of X-rays are of the same order of magnitude as the separation between atoms in a crystal- A. photo electric effect
- B. ionization
- C. shadow photograph
- D. any of above
Explanation: An X-ray photograph records the shadow pattern formed because different tissues absorb different amounts of X-ray radiation.
Correct answer: shadow photograph- A. Newton
- B. Einstein
- C. Raleigh
- D. Planks
Explanation: The relation θ = 1.22λ/D is the Rayleigh criterion for the angular resolution of a circular aperture, where θ is in radians, λ is the…
Correct answer: Raleigh- A. C = 4fd
- B. C = 8fd
- C. C = 16fd
- D. C = 5/2fd
Explanation: In Michelson's rotating-mirror method, light travels a total distance of 2d, and the mirror turns through one-eighth of a revolution…
Correct answer: C = 16fd- A. 300km
- B. 200km
- C. 100km
- D. 20km
Explanation: In newer optical-fibre communication systems, repeaters can commonly be spaced about 100 km apart because the signal suffers relatively…
Correct answer: 100km- A. to produce parallel beams of light
- B. to filter the light rays
- C. to make them
- D. no function
Explanation: A collimator uses a slit and a converging lens to convert light from the slit into a parallel beam.
Correct answer: to produce parallel beams of light