The magnetic moment of an electron (e) revolving in an orbit around nucleus with an orbital angular momentum is given by:
\(\vec{\mu L}\)=\(\frac{\vec{eL}}{2m}\)
\(\vec{\mu L}\)=\(-\frac{\vec{eL}}{2m}\)
\(\vec{\mu L}\)=−\(\frac{\vec{eL}}{m}\)
\(\vec{\mu L}\)=\(\frac{\vec{2eL}}{m}\)
The Correct Option is B
Solution and Explanation
∵ \(\vec{\mu }\)=\(\frac{\vec{qL}}{2m}\)
\(\vec{\mu }\)=\(-\frac{\vec{eL}}{2m}\)
Top Questions on Electromagnetic induction
- If $ \epsilon_0 $ denotes the permittivity of free space and $ \Phi_E $ is the flux of the electric field through the area bounded by the closed surface, then the dimension of $ \epsilon_0 \frac{d\Phi_E}{dt} $ are that of:
- JEE Main - 2025
- Physics
- Electromagnetic induction
- A coil has 100 turns, each of area \( 0.05 \, \text{m}^2 \) and total resistance \( 1.5 \, \Omega \). It is inserted at an instant in a magnetic field of \( 90 \, \text{mT} \), with its axis parallel to the field. The charge induced in the coil at that instant is:
- CBSE CLASS XII - 2025
- Physics
- Electromagnetic induction
- Which of the following devices is based on the principle of electromagnetic induction?
- Bihar Board XII - 2025
- Physics
- Electromagnetic induction
- State Lenz’s law. A rod MN of length \( L \) is rotated about an axis passing through its end M perpendicular to its length, with a constant angular velocity \( \omega \) in a uniform magnetic field \( \vec{B} \) parallel to the axis. Obtain an expression for emf induced between its ends.
- CBSE CLASS XII - 2025
- Physics
- Electromagnetic induction
- Which of the following statements is not correct for electromagnetic induction?
- CUET (UG) - 2025
- Physics
- Electromagnetic induction
Questions Asked in JEE Main exam
- If the equation of the parabola with vertex $\left(\frac{3}{2},\, 3\right)$ and the directrix $x + 2y = 0$ is
$$ ax^2 + by^2 - cxy - 30x - 60y + 225 = 0, $$ then $\alpha + \beta + \gamma$ is equal to:- JEE Main - 2025
- Calculus
- In a first order decomposition reaction, the time taken for the decomposition of reactant to one fourth and one eighth of its initial concentration are $ t_1 $ and $ t_2 $ (s), respectively. The ratio $ t_1 / t_2 $ will be:
- JEE Main - 2025
- Chemical Kinetics
- HA $ (aq) \rightleftharpoons H^+ (aq) + A^- (aq) $ The freezing point depression of a 0.1 m aqueous solution of a monobasic weak acid HA is 0.20 °C. The dissociation constant for the acid is Given: $ K_f(H_2O) = 1.8 \, \text{K kg mol}^{-1} $, molality ≡ molarity
- JEE Main - 2025
- Colligative Properties
20 mL of sodium iodide solution gave 4.74 g silver iodide when treated with excess of silver nitrate solution. The molarity of the sodium iodide solution is _____ M. (Nearest Integer value) (Given : Na = 23, I = 127, Ag = 108, N = 14, O = 16 g mol$^{-1}$)
- JEE Main - 2025
- Stoichiometry and Stoichiometric Calculations
- Which of the following binary mixture does not show the behavior of minimum boiling azeotropes?
- JEE Main - 2025
- Solutions
Concepts Used:
Magnetic Field
The magnetic field is a field created by moving electric charges. It is a force field that exerts a force on materials such as iron when they are placed in its vicinity. Magnetic fields do not require a medium to propagate; they can even propagate in a vacuum. Magnetic field also referred to as a vector field, describes the magnetic influence on moving electric charges, magnetic materials, and electric currents.
A magnetic field can be presented in two ways.
- Magnetic Field Vector: The magnetic field is described mathematically as a vector field. This vector field can be plotted directly as a set of many vectors drawn on a grid. Each vector points in the direction that a compass would point and has length dependent on the strength of the magnetic force.
- Magnetic Field Lines: An alternative way to represent the information contained within a vector field is with the use of field lines. Here we dispense with the grid pattern and connect the vectors with smooth lines.
Properties of Magnetic Field Lines
- Magnetic field lines never cross each other
- The density of the field lines indicates the strength of the field
- Magnetic field lines always make closed-loops
- Magnetic field lines always emerge or start from the north pole and terminate at the south pole.