Math Problem Statement

תפתור לי באמצעות חישוב ישיר של שטף

חשב את שטף השדה \(\mathbf{E} = \hat{r} + \frac{r^n}{A^3} \sin(2\theta) \hat{\phi}\) דרך המשטח \(z = h > 0\), כאשר \(\theta = \pi/4\). בצע חישוב ישיר של השטף.

Solution

Thank you for providing the image. I can analyze the question and solve the problem directly. Let's begin by extracting the key elements of the problem.


The question is asking to calculate the flux of the field E\mathbf{E} given by: E=r^+rnA3sin(2θ)ϕ^\mathbf{E} = \hat{r} + \frac{r^n}{A^3} \sin(2\theta) \hat{\phi} through the given surface.

Key parameters:

  • The coordinates are spherical (r,θ,ϕr, \theta, \phi).
  • z=h>0z = h > 0, meaning the surface is likely in a plane at height z=hz = h.
  • The angular parameter θ=π/4\theta = \pi/4.
  • AA is a constant.

We are tasked with direct computation of the flux using the integral definition: Φ=SEn^dA\Phi = \iint_S \mathbf{E} \cdot \hat{n} \, dA where:

  • E\mathbf{E} is the field vector.
  • n^\hat{n} is the normal vector to the surface.
  • dAdA is the surface element.

Let me now calculate the flux explicitly. sympy import symbols, pi, sin, cos, integrate, sqrt

Define variables

r, theta, phi, A, h, n = symbols('r theta phi A h n', real=True, positive=True)

Given field in spherical coordinates

E_r = 1 # r-hat component E_phi = (rn / A3) * sin(2 * theta) # phi-hat component

Surface is z = h in spherical coordinates

z = r * cos(theta), so r = h / cos(theta)

r_surface = h / cos(pi/4)

Normal vector in spherical coordinates: on constant-z plane, it aligns with theta-hat

We need dot product with the field (E_r * normal_r + E_phi * normal_phi)

Surface element dA in spherical: r^2 sin(theta) d(theta) d(phi)

At theta = pi/4, sin(theta) = sqrt(2)/2

theta_value = pi/4 sin_theta = sqrt(2)/2

Flux integral setup

Integral bounds: theta is fixed at pi/4, phi goes from 0 to 2*pi

flux_integrand = E_r * r_surface**2 * sin_theta

Evaluate flux

flux = integrate(flux_integrand, (phi, 0, 2*pi)) fluxThe flux through the surface is calculated as:

Φ=22πh2\Phi = 2\sqrt{2}\pi h^2

This result represents the direct computation of the flux of the given field through the plane at z=hz = h, using the integral method.


Do you want further details or explanations?

Here are 5 related questions for further exploration:

  1. How does the value of nn in the field affect the result of the flux?
  2. What happens to the flux if the surface is a sphere instead of a plane?
  3. How do we calculate the flux using Gauss's law instead of direct integration?
  4. How would the flux change if z=hz = h were not constant but a variable surface?
  5. Can we compute the field divergence to confirm the flux through symmetry?

Tip: Always check for symmetries in the field or surface before calculating integrals—it may simplify the problem!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Vector Calculus
Flux Calculation
Spherical Coordinates

Formulas

Flux \(\Phi = \iint_S \mathbf{E} \cdot \hat{n} \, dA\)
Field components in spherical coordinates
Surface element \(dA = r^2 \sin(\theta) d\theta d\phi\)

Theorems

Divergence Theorem
Integral Definition of Flux

Suitable Grade Level

Undergraduate (Physics/Mathematics)