Question

An echo is heard from a building 0.39 s after you shout ""hello."" How many feet away is the building if the air temperature is 24.2°C?

Answer 1

To determine the distance to the building from which an echo is heard 0.39 seconds after shouting, you can use the formula Distance = (Speed of Sound) x (Time of Echo / 2). Assuming the speed of sound at 24.2°C is about 1135 ft/s, the building is approximately 221.33 feet away.

Step-by-step explanation:

An echo is the sound heard after it reflects off a surface and returns to the listener. The time it takes for the echo to return is directly related to the distance of the reflecting surface. The speed of sound varies with temperature, and at 24.2°C, the speed of sound is approximately 346 meters per second (about 1135 ft/s). To calculate the distance to the building, you would use the formula:

Distance = (Speed of Sound) x (Time of Echo / 2). The division by 2 is because the time includes the journey to the building and back. Thus, a 0.39-second echo would mean the building is approximately:

Distance = 1135 ft/s x 0.39 s / 2 ≈ 221.33 feet away.