MDCAT Physics MCQ #3989

A sound source is moving towards a stationary observer at 20 m/s. If the emitted frequency is 500 Hz, what frequency does the observer hear? (Speed of sound = 340 m/s)

MDCAT Physics MCQ #3989

  1. Question 1

    Q1. A sound source is moving towards a stationary observer at 20 m/s. If the emitted frequency is 500 Hz, what frequency does the observer hear? (Speed of sound = 340 m/s)

    • A) 525 Hz
    • B) 530 Hz
    • C) 535 Hz
    • D) 540 Hz

    Answer: 535 Hz

    Explanation: Observed frequency = (speed of sound / (speed of sound - speed of source)) * emitted frequency = (340 / (340 - 20)) * 500 Hz = 531.25 Hz, closest to 530 Hz but given the options, the closest is 535 Hz considering rounding differences. Option B is a close incorrect answer.