JEE Exam  >  JEE Questions  >  A sound source emits frequency of 175 Hz when... Start Learning for Free
A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.
    Correct answer is '5'. Can you explain this answer?
    Verified Answer
    A sound source emits frequency of 175 Hz when moving towards a rigid w...
    Frequency of direct sound heared by observer 
    Wave length of reflected sound wave  
    No. of beats heared by person
    View all questions of this test
    Most Upvoted Answer
    A sound source emits frequency of 175 Hz when moving towards a rigid w...
    Solution:

    Given:
    Frequency of sound emitted by the source, f = 175 Hz
    Velocity of the source towards the wall, Vs = 5 m/s
    Velocity of the observer away from the wall, Vo = 5 m/s
    Velocity of sound, v = 355 m/s

    To find:
    The number of beats per second heard by the observer

    Explanation:
    When a sound source moves towards a stationary observer, the frequency of the sound waves received by the observer is higher than the frequency emitted by the source. This is known as the Doppler effect. Similarly, when the observer moves away from the sound source, the frequency of the sound waves received by the observer is lower than the frequency emitted by the source.

    In this case, both the source and observer are moving, and the wall is stationary. The frequency of the sound waves received by the observer is given by the following formula:

    f' = f (v + Vo) / (v - Vs)

    Where, f' is the frequency received by the observer, f is the frequency emitted by the source, v is the velocity of sound, Vs is the velocity of the source towards the wall, and Vo is the velocity of the observer away from the wall.

    Substituting the given values in the formula, we get:

    f' = 175 (355 + 5) / (355 - 5)
    f' = 180 Hz

    Therefore, the frequency received by the observer is 180 Hz.

    Now, the number of beats heard per second is given by the difference between the frequency received and the frequency emitted by the source. That is,

    Number of beats per second = |f' - f|

    Substituting the given values, we get:

    Number of beats per second = |180 - 175|
    Number of beats per second = 5

    Therefore, the number of beats heard per second by the observer is 5.

    Conclusion:
    Hence, the correct answer is 5.
    Explore Courses for JEE exam

    Similar JEE Doubts

    A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer?
    Question Description
    A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer? for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer? covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer?.
    Solutions for A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer? in English & in Hindi are available as part of our courses for JEE. Download more important topics, notes, lectures and mock test series for JEE Exam by signing up for free.
    Here you can find the meaning of A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer?, a detailed solution for A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer? has been provided alongside types of A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A sound source emits frequency of 175 Hz when moving towards a rigid wall with speed 5 m/s and observer is moving away from wall with same speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s] Source is in between observer and wall.Correct answer is '5'. Can you explain this answer? tests, examples and also practice JEE tests.
    Explore Courses for JEE exam

    Top Courses for JEE

    Explore Courses
    Signup for Free!
    Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
    10M+ students study on EduRev