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.
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665 questions · page 27 of 34
- A. Constructive interference
- B. Destructive interference
- C. Different frequency range
- D. None of these
Explanation: Constructive interference occurs when the path difference between two sounds is an integral multiple of the wavelength because the waves…
Correct answer: Constructive interference- A. Shift theorem
- B. Doppler's shift
- C. Polarization
- D. None of these
Explanation: The Doppler's effect, also known as Doppler shift, explains the change in frequency of waves emitted by a moving source, which is crucial…
Correct answer: Doppler's shift- A. Quantization of frequency
- B. Resonance
- C. Photo-electric effect
- D. None of these
Explanation: A wave with a discrete set of frequencies indicates quantization of frequency, where specific frequencies are present.
Correct answer: Quantization of frequency- A. 40 m/sec
- B. 40 cm/sec
- C. 80 m/sec
- D. 100 m/sec
Explanation: The correct answer is 40 m/sec. The speed of a wave in a medium is given by the formula: speed = frequency x wavelength.
Correct answer: 40 m/sec- A. Interference
- B. Diffraction
- C. Polarization
- D. Rarefraction
Explanation: Newton's rings demonstrate the phenomenon of interference, where an interference pattern is created by the reflection of light between two…
Correct answer: Interference- A. Yellow
- B. Violet
- C. Indigo
- D. Red
Explanation: When light is incident on a diffraction grating, the amount of deviation is directly proportional to the wavelength of light.
Correct answer: Red- A. Diffraction sends red rays to the earth at these times
- B. Scattering due to dust particles and air molecules is responsible for this effect
- C. Refraction is responsible for this effect
- D. Polarization is responsible for this effect
Explanation: During sunset and sunrise, sun is near the horizon and therefore sunlight has to travel larger distance in the atmosphere.
Correct answer: Scattering due to dust particles and air molecules is responsible for this effect- A. Simple reflection
- B. Double refraction
- C. Scattering of light
- D. All of these
Explanation: Plane polarized light can be produced by all of the methods listed - simple reflection, double refraction, and scattering of light.
Correct answer: All of these- A. Reflection
- B. Interference
- C. Double refraction
- D. Scattering of light
Explanation: Interference does not result in the polarization of light because it involves the meeting of waves to form a new wave of different…
Correct answer: Interference- A. Light waves are longitudinal
- B. Light waves are transverse
- C. Light waves are not transverse
- D. Light waves are longitudinal as well as
Explanation: Polarization of light confirms that light waves are transverse in nature, with vibrations restricted to a single plane.
Correct answer: Light waves are transverse- A. Wave theory
- B. Particle theory
- C. Both wave and particle theories
- D. None of these
Explanation: The correct answer is 'Both wave and particle theories'. Light demonstrates properties of both wave and particle theories.
Correct answer: Both wave and particle theories- A. Allows us to find the focal length of thick lens
- B. Gives us the magnifying power of microscope
- C. Is a geometrical method to find the position of a wave front
- D. Is used to determine the velocity of light
Explanation: Huygen's principle is a fundamental concept in optics that describes how every point on a wavefront acts as a source of secondary…
Correct answer: Is a geometrical method to find the position of a wave front- A. Velocity
- B. Amplitude
- C. Frequency
- D. Wavelength
Explanation: Frequency of light remains unchanged when it travels from vacuum to water because frequency is independent of the medium.
Correct answer: Frequency- A. Mechanical waves
- B. Electromagnetic
- C. Matter waves
- D. None of these
Explanation: Electromagnetic waves do not require a medium for their propagation, unlike mechanical and matter waves which do.
Correct answer: Electromagnetic- A. Interference
- B. Polarization
- C. Diffraction
- D. Reflection
Explanation: Diffraction occurs when light waves bend around the edges of an object or obstacle, demonstrating wave behavior.
Correct answer: Diffraction- A. Chistian Huygens
- B. Francesco Gimaldi
- C. Thomas Young
- D. Augustin Fresnel
Explanation: Francesco Gimaldi is credited with discovering the phenomenon of light diffraction and noting its similarity to wave behavior.
Correct answer: Francesco Gimaldi- A. Wave
- B. Particle
- C. Both wave and particle
- D. None of these
Explanation: When discussing the behavior of light in terms of refraction and reflection, it is best understood as a wave.
Correct answer: Wave- A. Wave
- B. Particle
- C. Both wave and particle
- D. None of these
Explanation: The correct answer is 'Particle.' The photoelectric effect demonstrates the particle nature of light, which is why considering light to…
Correct answer: Particle- A. Energy and momentum
- B. Energy
- C. Momentum
- D. None of these
Explanation: Electromagnetic waves transport both energy and momentum. Energy is carried as the wave propagates through space, and momentum is…
Correct answer: Energy and momentum- A. Light travels in straight line
- B. Light has dual nature
- C. All points on primary wave front are source of secondary wavelet
- D. None of these
Explanation: Huygens principle enables us to determine the position and shape of a new wavefront by considering each point on the primary wavefront as…
Correct answer: All points on primary wave front are source of secondary wavelet