An observer is 660 m away from a thundercloud. The sound of thunder reaches him after (V = 330 m/s)
A20 seconds only
B5 seconds only
C0.5 seconds only
D2 seconds
Answer & Solution
Correct answer: D. 2 seconds
1. Time taken = distance / speed.
2. = 660 / 330.
3. = 2 seconds.
4. So sound reaches the observer after 2 s.
_Source: Selina Concise Physics Class 9, Ch 8 Sound (Mistral OCR'd PDF), section on lightning and thunder_
Related questions
In which of the following media does sound travel the fastest?Sound travels fastest through which of the following media?A sound wave has wavelength 0.66 m in air where speed of sound is 330 m/s. Its frequency iThe wavelength of a sound wave of frequency 660 Hz travelling at 330 m/s isUltrasonic waves are used in industry toUltrasonic waves are used in medicine forA bat emits ultrasonic pulses at 50 kHz to navigate. This method is calledLightning and thunder reach an observer at different times because