Q. An echo repeats two syllables. If the velocity of sound is $330ms^{- 1}$, then the distance of the reflecting surface is
A) 66.0 m
B) 33.0 m
C) 99.0 m
D) 16.5 m
Explanation
(a) Time taken for two syllables $t = \frac{2}{5}s$
$x + x = v \times t = 330 \times \frac{2}{5}$
$\therefore x = 66m$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.