Question
Explain the sources of electric and magnetic field.
✓
Answer
→A steady charge Q produces an electric field (from chapter-1) E.
→The electric field on point at a distance $r$ from the point charge $Q$ is
$\therefore \overrightarrow{ E }=\frac{1}{4 \pi \varepsilon_0} \cdot \frac{ Q }{r^2} \cdot \hat{r}\left(\text { or } \frac{ KQ }{r^2} \hat{r}\right)$
→Apart from being dependent on every point in space, the electric field can vary with time.
→ If more than one electric field converge near a point, the resultant electric field at the point is equal to the vector sum of all the electric field.
→Just as static charges produce an electric field, moving charges or current produces a magnetic field denoted by $\overrightarrow{ B }(\vec{r})$.
→Similar to electric field, the magnetic field can also be defined at every point in space and it also follows the principle of superposition.
→The electric field on point at a distance $r$ from the point charge $Q$ is
$\therefore \overrightarrow{ E }=\frac{1}{4 \pi \varepsilon_0} \cdot \frac{ Q }{r^2} \cdot \hat{r}\left(\text { or } \frac{ KQ }{r^2} \hat{r}\right)$
→Apart from being dependent on every point in space, the electric field can vary with time.
→ If more than one electric field converge near a point, the resultant electric field at the point is equal to the vector sum of all the electric field.
→Just as static charges produce an electric field, moving charges or current produces a magnetic field denoted by $\overrightarrow{ B }(\vec{r})$.
→Similar to electric field, the magnetic field can also be defined at every point in space and it also follows the principle of superposition.
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