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Name: brett
Status: N/a
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993

Why is an echo weaker than the original sound?

An echo is a signal that has been propagated through the air from some object whose surface created a reflection of the signal. Whenever a signal propagates in space, it spreads out with some of the signal going off in different directions away from the original direction. The signal left on the original beam is less than the whole beam that started so the energy in the received beam is always less. For a point source the energy per unit area drops off as the inverse square of the distance.

Sam Bowen

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