search
arrow-left Previous
Next arrow-right
Q: To hear distinct echo the time interval between the original sound and the reflected sound must be -
  • A. 1 second
  • B. 0. 1 second
  • C. 0.02 second
  • D. 2 seconds
Correct Answer: Option B - Gap between original and reflected sounds. Due to persistence of hearing, we keep the gap for hearing a sound for 0.1 s, even after the source of sound has stopped vibrating. So, if we want to hear distinct echo, the reflected sound must reach to the ear in 0.1 s after.
B. Gap between original and reflected sounds. Due to persistence of hearing, we keep the gap for hearing a sound for 0.1 s, even after the source of sound has stopped vibrating. So, if we want to hear distinct echo, the reflected sound must reach to the ear in 0.1 s after.

Explanations:

Gap between original and reflected sounds. Due to persistence of hearing, we keep the gap for hearing a sound for 0.1 s, even after the source of sound has stopped vibrating. So, if we want to hear distinct echo, the reflected sound must reach to the ear in 0.1 s after.