(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A spherical wave with a wavelength of 2.0 m is emitted from the origin. At one instant of time, the phase at r=4.0m is pi radians. At that instant, what is the phase at r=3.5m?

2. Relevant equations

D(x,y,z,t)=Asin(kr-wt+phi)

k=(2pi)/(lambda)

w=(2pi)/T

3. The attempt at a solution

(kr-wt+(phi))=phase constant

D(x,y,z)=displacement, or here, radius

A cancels and doesn't matter.

4/(pi)=3.5/x

x=3.5(pi)/4 <---- which is wrong.

So then I tried subtracting the equations...

4=Asin(pi)

-3.5=-Asinx

.5=Asin(pi)-Asinx

.5=Asinx <---- Then I didn't know what to do with it. Help please?

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# Homework Help: Spherical Wave - What is the phase?

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