In spherical coordinates for the region $x^2+y^2+z^2\geq1$, $x^2+y^2=z^2\leq4$, $z\geq\sqrt{x^2+y^2}$, why does $\psi$ range from $0$ to $\pi/2$?

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I was given the following task calculate:

$\iiint_V{(xz^2+z)dxdydz} \space$ where $\space V = \begin{cases} x^2+y^2+z^2\geq1 & \text{inner sphere} \\ x^2+y^2+z^2\leq4 & \text{sphere} \\ z\geq \sqrt{x^2+y^2} & \text{cone} \\ \end{cases}$

I calculated the spherical coordinates :

$$\begin{cases} x=r\cos\phi{}\cos\psi{} \\ y=r\sin\phi{}\cos\psi \\ z=r\sin\psi \\ \end{cases}$$

$$[J]=r^2\cos\psi$$

$$\iiint_V{(xz^2+z)dxdydz}=\iiint_\Omega [r\cos\phi \cos\psi(r\sin\psi)^2+ r\sin\psi] r^2\cos\psi] drdydz$$

$$\Omega = \begin{cases} 0\leq \phi \leq 2\pi \\ 0 \leq\psi \leq \frac{\pi}{2} \\ 1 \leq r \leq 2 \\ \end{cases}$$

I did the further computations and solved the problem but I am looking for an explanation why is :

$$0 \leq\psi \leq \frac{\pi}{2}$$

Are my assumptions correct?

I have found a similar example in a book and I am looking for an explanation of $\Omega$ and checking if it is correct.

Here is my whole solution but what I need help with is a range of $\psi$ in $\Omega$ and why is it to $\frac{\pi}{2}$

Scan of my solution

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The constraint $z>\sqrt {x^2 +y^2}$ becomes $r\sin\psi > r\cos\psi$

$\tan \psi > 1$

$\frac \pi 4 < \psi < \frac\pi 2$