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kow [346]
3 years ago
11

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 3.7s\; s after shouting. The speed of sound in air is 343 m/s\rm m/s. Determine the length of the lake. Express your answer to two significant figures and include the appropriate units.
Physics
1 answer:
Nataliya [291]3 years ago
8 0

To solve the exercise it is necessary to take into account the definition of speed as a function of distance and time, and the speed of air in the sound, as well

v=\frac{d}{t}

Where,

V= Velocity

d= distance

t = time

Re-arrange the equation to find the distance we have,

d=vt

Replacing with our values

d= (343)(3.7)

d= 1269.1m

It is understood that the sound comes and goes across the entire lake therefore, the length of the lake is half the distance found, that is

L_{lake} = \frac{d}{2}

L_{lake} = \frac{1269.1}{2}

L_{lake} = 634.55m

Therefore the length of the lake is 634,55m

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