Consider the circular loop having current $i$ and with central point $O$. The magnetic field at the central point $O$ is
- $\frac{2\mu_0 i}{3\pi R} $ acting downward
- $ \frac{5\mu_0i}{12R}$ acting downward
- $ \frac{6\,\mu_0 i}{11 R} $ acting downward
- $\frac{3\mu_0 i}{7R}$ acting upward
The Correct Option is B
Solution and Explanation
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\[ V(x) = \begin{cases} V_0 + \frac{1}{2} m \omega_{0P}^2 x^2 & \quad \text{if } x > 0 \\\infty & \quad \text{if } x \leq 0 \end{cases}\]
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- Transcription
Concepts Used:
Magnetism & Matter
Magnets are used in many devices like electric bells, telephones, radio, loudspeakers, motors, fans, screwdrivers, lifting heavy iron loads, super-fast trains, especially in foreign countries, refrigerators, etc.
Magnetite is the world’s first magnet. This is also called a natural magnet. Though magnets occur naturally, we can also impart magnetic properties to a substance. It would be an artificial magnet in that case.
Read More: Magnetism and Matter
Some of the properties of the magnetic field lines are:
- The lines and continuous and outside the magnet, the field lines originate from the North pole and terminate at the South pole
- They form closed loops traversing inside the magnet.
- But here the lines seem to originate from the South pole and terminate at the North pole to form closed loops.
- More number of close lines indicate a stronger magnetic field
- The lines do not intersect each other
- The tangent drawn at the field line gives the direction of the field at that point.