The quantum theory of light was given by ________.
  • a)
    Einstein
  • b)
    Plank
  • c)
    Newton
  • d)
    Faraday
Correct answer is option 'B'. Can you explain this answer?

Knowledge Hub answered  •  13 hours ago
  • The quantum theory of light was given by Plank.
  • The quantum theory of light states that all objects emit energy in the form of electromagnetic waves.
  • These waves are generated by the oscillations of charge found in the atom and molecules.
  • Max Karl Ernst Ludwig Planck's quantum theory of light states that the energy associated with atomic and molecu... more

To hear a distinct echo the time interval between the original sound and the reflected sound must be at least ________.
  • a)
    1 second
  • b)
    0.1 second
  • c)
    0.2 second
  • d)
    2 second
Correct answer is option 'B'. Can you explain this answer?

Learners World answered  •  yesterday
  • Echo: It is the repetition of the original sound because of reflection by some surface.
  • Our brain retains a sound for 0.1 s. Thus, for us to be able to hear a distinct echo, the sound should take more than 0.1 s after starting from the source to get reflected and come back to us.

Fetching relevant content for you