A magnetic dipole in a constant magnetic field has :
- maximum potential energy when the torque is maximum.
- zero potential energy when the torque is minimum.
- zero potential energy when the torque is maximum.
- minimum potential energy when the torque is maximum.
The Correct Option is C
Solution and Explanation
$\tau$ = PE sin $\theta$
$\tau_{max}$ when $\theta = 90^{\circ}$
PE $= 0$
Top Questions on Magnetism and matter
- A current-carrying loop can be considered as a magnetic dipole placed along its axis. Explain.
- CBSE CLASS XII - 2025
- Physics
- Magnetism and matter
- Obtain the relation for magnetic dipole moment \( \mathbf{M} \) of a current-carrying coil. Give the direction of \( \mathbf{M} \).
- CBSE CLASS XII - 2025
- Physics
- Magnetism and matter
- A charged particle moves in a magnetic field with velocity $ v $ perpendicular to the field $ B $. The radius of the circular path is $ r $. Which of the following expressions gives the charge $ q $ of the particle?
- BITSAT - 2025
- Physics
- Magnetism and matter
- Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A) : Magnetic monopoles do not exist.
Reason (R) : Magnetic field lines are continuous and form closed loops.
In the light of the above statements, choose the most appropriate answer from the options given below :- JEE Main - 2025
- Physics
- Magnetism and matter
- The percentage increase in magnetic field $ B $ when space within a current-carrying solenoid is filled with magnesium (magnetic susceptibility $ \chi_{mg} = 1.2 \times 10^{-5} $) is:
- JEE Main - 2025
- Physics
- Magnetism and matter
Questions Asked in JEE Main exam
The least acidic compound, among the following is
- JEE Main - 2025
- Organic Chemistry
Choose the correct set of reagents for the following conversion:
- JEE Main - 2025
- Organic Chemistry
- JEE Main - 2025
- Organic Chemistry
- In a group of 3 girls and 4 boys, there are two boys \( B_1 \) and \( B_2 \). The number of ways in which these girls and boys can stand in a queue such that all the girls stand together, all the boys stand together, but \( B_1 \) and \( B_2 \) are not adjacent to each other, is:
- JEE Main - 2025
- Permutations
A bead of mass \( m \) slides without friction on the wall of a vertical circular hoop of radius \( R \) as shown in figure. The bead moves under the combined action of gravity and a massless spring \( k \) attached to the bottom of the hoop. The equilibrium length of the spring is \( R \). If the bead is released from the top of the hoop with (negligible) zero initial speed, the velocity of the bead, when the length of spring becomes \( R \), would be (spring constant is \( k \), \( g \) is acceleration due to gravity):
- JEE Main - 2025
- Fluid Mechanics
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.