Answer in Physics for Jerick #172741

1.     A hiker determines the length of a lake by listening for the echo of her shout reflected by a cliff at the far end of the lake. She hears the echo 2.5 s after shouting. Estimate the length of the lake.

The distance traveled by the sound can be found as follows:

“d=vt.”

From the other hand, the total distance from the hiker to the cliff and back equals:

“d=2l.”

Then, we get:

“2l=vt,”“l=dfrac{vt}{2}=dfrac{343 dfrac{m}{s}cdot2.5 s}{2}=430 m.”