Question.
An echo is returned in $3 \mathrm{~s}$. What is the distance of the reflecting surface from the source, given that the speed of sound is $342 \mathrm{~ms}^{-1}$ ?
An echo is returned in $3 \mathrm{~s}$. What is the distance of the reflecting surface from the source, given that the speed of sound is $342 \mathrm{~ms}^{-1}$ ?
Solution:
Given, speed of sound, $\mathrm{v}=342 \mathrm{~m} \mathrm{~s}^{-1}$;
time taken for hearing the echo, $\mathrm{t}=3 \mathrm{~s}$;
distance of the reflecting surface, $\mathrm{s}=$ ?
Now, $\mathrm{s}=\frac{\mathrm{v}}{2}=\frac{342}{2}=\mathbf{5 1 3} \mathbf{~ m}$
Given, speed of sound, $\mathrm{v}=342 \mathrm{~m} \mathrm{~s}^{-1}$;
time taken for hearing the echo, $\mathrm{t}=3 \mathrm{~s}$;
distance of the reflecting surface, $\mathrm{s}=$ ?
Now, $\mathrm{s}=\frac{\mathrm{v}}{2}=\frac{342}{2}=\mathbf{5 1 3} \mathbf{~ m}$