1. The problem statement, all variables and given/known data Suppose sound wave is emitted uniformly in all directions by a speaker. At a distance of 1.1m, the amplitude of it sound is 1.2x10^-8m What is the amplitude of sound at a distance of 1.7m? 3. The attempt at a solution What I'm confused is why does the amplitude of sound change? Isn't intensity = Power/Area? So at a greater distance, it just means that intensity is lowered. But power from a source is always constant isn't that right? And since power is proportional to amplitude squared, why does the amplitude decrease? am i missing out something? The answer is 7.8x10^-9 using the relationship of intensity proportional to amplitude^2 and 1/r^2 if you are curious.