Magnetism: Difference between revisions
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== Calculate Field == | == Calculate Field == | ||
<math> | <math> | ||
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\hat{r}}{ r^2 } | \hat{r}}{ r^2 } | ||
</math> | </math> | ||
Any component going along the direction of current is cancelled by cross | |||
product. '''Something else'''. Therefore, | |||
Unlike electric fields, there is no beginning or end to magnetic fields. | |||
Consider a close surface: The magnetic flux is always 0. | |||
<math> | |||
\oiint_S \vec{B} \cdot d \vec{s} = 0 \\ | |||
\oint \vec{B} \cdot d \vec{l} \neq 0 | |||
</math> | |||
Recall that a point charge produces an electric field that points | |||
radially outward based on Coulomb's Law. This results in Gauss's Law and | |||
circulation being zero. | |||
Revision as of 21:38, 28 February 2024
Magnetic Field
A moving charge causes a magetic field, following the right hand rule: Your thumb pointing towards the direction of movement of the positive charge, and your other fingers wrap around to indicate the direction of the magnetic field.
A circulating current forms a magnetic dipole.
Calculate Field
Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{B} (\vec{r}) = \frac{ \mu_0 }{ 4 \pi } \frac{ I_1 d\vec{l}_1 \times \hat{r}}{ r^2 } }
Any component going along the direction of current is cancelled by cross product. Something else. Therefore,
Unlike electric fields, there is no beginning or end to magnetic fields. Consider a close surface: The magnetic flux is always 0. Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \oiint_S \vec{B} \cdot d \vec{s} = 0 \\ \oint \vec{B} \cdot d \vec{l} \neq 0 }
Recall that a point charge produces an electric field that points radially outward based on Coulomb's Law. This results in Gauss's Law and circulation being zero.
