I have a question to solve - A boy heard a sound of frequency 100 Hz at a distance of 500 m from the source of sound. What is the speed of sound? What is the time period of oscillating particles of the medium? I have approached the below way : We know that speed = distance / time [1/T=Frequency) Hence speed = distance x Frequency = 500 m x 100 Hz = 50 km Now given that Frequency is 100 Hz which is nothing but 100 oscillation per sec = So 1 oscillation = 1 / 100 = 0.01 sec. Please let me know if my answers are correct?