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An echo is heard from a building 0.485 s after you shout "hello." How many feet away is the building if the air temperature is 30.6°C?

User Ghloogh
by
6.8k points

1 Answer

2 votes

Answer: 84.63 m

Step-by-step explanation:

The speed of sound in the air, at
0 \°C is
331.5 m/s, and for each degree Celsius the temperature rises, the speed of the sound increases by
0.6 m/s. So, if we estimate the speed of sound at
30 \°C it will be
349 m/s.

On the other hand, the speed of sound
V is defined as the distance traveled
d in a especific time
t:


V=(d)/(t)

Where:


V=349 m/s is the speed of sound


t=(0.485 s)/(2)=0.2425 s is half the time the sound wave travels since you say "hello", the sound wave hits the building and then returns to you


d is the distance between you and the building


349 m/s=(d)/(0.2425 s)

Finding
d:


d=(349 m/s)(0.2425 s)

Finally:


d=84.63 m

User Philroy
by
7.2k points