002的旋度
旋度是一个向量,由以下公式给出:
$\nabla \times \vec{F} = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \ \frac{\partial}{\partial x} & \frac{\partial}{\partial y} & \frac{\partial}{\partial z} \ F_x & F_y & F_z \end{vmatrix}$
其中,$\hat{i}$、$\hat{j}$、$\hat{k}$是单位向量,$\frac{\partial}{\partial x}$、$\frac{\partial}{\partial y}$、$\frac{\partial}{\partial z}$是偏微分算符,$F_x$、$F_y$、$F_z$是向量$\vec{F}$在$x$、$y$、$z$方向上的分量。
在这个问题中,向量$\vec{F}=(0,0,2)$,因此:
$\nabla \times \vec{F} = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \ \frac{\partial}{\partial x} & \frac{\partial}{\partial y} & \frac{\partial}{\partial z} \ 0 & 0 & 2 \end{vmatrix}$
对于第一行,$\hat{i}$的系数为0,因此可以忽略。对于第二行,$\hat{j}$的系数为$-\frac{\partial}{\partial z}$,因此需要对$F_z$进行偏微分。对于第三行,$\hat{k}$的系数为$\frac{\partial}{\partial y}$,因此需要对$F_y$进行偏微分。因此:
$\nabla \times \vec{F} = \left(\frac{\partial F_z}{\partial y}-\frac{\partial F_y}{\partial z}\right)\hat{i} + \left(\frac{\partial F_x}{\partial z}-\frac{\partial F_z}{\partial x}\right)\hat{j} + \left(\frac{\partial F_y}{\partial x}-\frac{\partial F_x}{\partial y}\right)\hat{k}$
由于$F_x$和$F_y$都是0,因此$\frac{\partial F_x}{\partial z}$、$\frac{\partial F_y}{\partial x}$和$\frac{\partial F_y}{\partial z}$都是0。而$\frac{\partial F_z}{\partial y}=0$,$\frac{\partial F_z}{\partial x}=0$,因此:
$\nabla \times \vec{F} = -\frac{\partial F_y}{\partial z}\hat{i} + \frac{\partial F_x}{\partial z}\hat{j} + 0\hat{k}$
由于$F_x$和$F_y$都是0,因此$\frac{\partial F_x}{\partial z}$和$\frac{\partial F_y}{\partial z}$都是0。因此:
$\nabla \times \vec{F} = 0\hat{i} + 0\hat{j} + 0\hat{k} = \vec{0}$
因此,(0,0,2)的旋度是0
原文地址: https://www.cveoy.top/t/topic/huR2 著作权归作者所有。请勿转载和采集!