• A source of sound is moving eastward in still air. Wavelength of the waves to the east of the source is $λ_E$ and to the west of the source is $λ_W$
    A) $λ_E=λ_W$ B) $λ_E<λ_W$ C) $λ_E>λ_W$ D) Any of these
  • A source of sound is moving eastward in air blowing eastward. Wavelength of the waves to the east of the source is $λ_E$ and to the west of the source is $λ_W$
    A) $λ_E=λ_W$ B) $λ_E<λ_W$ C) $λ_E>λ_W$ D) Any of these
  • A source of sound is moving eastward in still air at a speed greater than the speed of sound in the medium. Wavelength of the waves in front of the source is $λ_F$ and to the back of the source is $λ_B$
    A) $λ_F=λ_B$ B) $λ_F<λ_B$ C) $λ_F>λ_B$ D) None of these
  • A boat is moving in a large lake at a speed greater than the speed of the waves on the surface of water.
    A) waves in the form of ripples spread out in all directions.
    B) waves in the form of ripples spread out only in the forward direction.
    C) A triangular wake is formed on the water's surface with a thin leading edge
    D) A triangular wake is formed on the water's surface with a thick leading edge.
  • An observer is moving towards a stationary source.
    A) wave length of the waves ahead of him will be smaller than the wavelength of the waves behind him.
    B) wave length of the waves ahead of him will be greater than the wavelength of the waves behind him.
    C) wave length of the waves ahead of him and the wavelength of the waves behind him will be same.
    D) Any of these depending on the frequency of the source.
  • When a vibrating tuning fork of frequency n moves in air.
    A) It starts vibrating at a frequency less than n
    B) It starts vibrating at a frequency greater than n.
    C) frequency of vibration may be less than or greater than n.
    D) frequency of vibration does not change as it moves.
  • A boat is moving in a large lake at a speed greater than the speed of the waves on the surface of water.
    A) waves in the form of ripples spread out in all directions.
    B) waves in the form of ripples spread out only in the forward direction.
    C) A triangular wake is formed on the water's surface with a thin leading edge
    D) A triangular wake is formed on the water's surface with a thick leading edge.
  • An observer is moving towards a stationary source.
    A) wave length of the waves ahead of him will be smaller than the wavelength of the waves behind him.
    B) wave length of the waves ahead of him will be greater than the wavelength of the waves behind him.
    C) wave length of the waves ahead of him and the wavelength of the waves behind him will be same.
    D) Any of these depending on the frequency of the source.
  • When a vibrating tuning fork of frequency n moves in air.
    A) It starts vibrating at a frequency less than n
    B) It starts vibrating at a frequency greater than n.
    C) frequency of vibration may be less than or greater than n.
    D) frequency of vibration does not change as it moves.