Converting integral into equivalent in spherical coordinates

Smily

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Joined
May 27, 2006
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I dont know how to solve this problem.

Convert the integral:

. . .[pi/2-integral-pi][0-integral-2][0-integral-(4-r^2)^(1/2)] r^2 cos(theta) dz dr d(theta)

...to a equivalent integral in spherical coordinates.

I know that:

. . .x = p sin(theta) cos(theta)
. . .y = p sin(theta) sin(theta)
. . .z = p cos(theta)
. . .p = 2 cosQ
. . .r = 2 cos(theta)

But I don't know how to convert it. Can somebody help me please? :roll:
 
Use r=ρsin(ϕ)\displaystyle r={\rho}sin({\phi}) to find your ϕ\displaystyle {\phi} limits.

2=2sin(ϕ)ϕ=π2\displaystyle 2=2sin({\phi})\Rightarrow{\phi}=\frac{\pi}{2}

Of course, you know ρ=2\displaystyle {\rho}=2

Theta stays the way it is.


\(\displaystyle \L\\\int_{\frac{\pi}{2}}^{\pi}\int_{0}^{\frac{\pi}{2}}\int_{0}^{2}{\rho}^{3}sin^{2}({\phi})cos({\theta})d{\rho}d{\phi}d{\theta}\)
 
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