One of the two small circular coils (neither having any self-inductance) is suspended with a $V$-shaped copper wire,with its plane horizontal. The other coil is placed just below the first one with its plane horizontal. Both coils are connected in series with a $dc$ supply. The coils are found to attract each other with a force. Which one of the following statements is incorrect?
- ABoth the coils carry currents in the same direction.
- BCoils will attract each other,even if the supply is an $ac$ source.
- CForce is proportional to $d^{-1}$.
- DForce is proportional to $d^{-2}$.
Explore More
Similar Questions
$A$ very long wire $ABDMNDC$ is shown in the figure carrying current $I$. $AB$ and $BC$ parts are straight,long,and at a right angle. At $D$,the wire forms a circular turn $DMND$ of radius $R$. $AB$ and $BC$ parts are tangential to the circular turn at $N$ and $D$. The magnetic field at the centre of the circle is
DifficultJEE MAIN 2020
View SolutionTwo parallel beams of electrons moving in the same direction produce a mutual force:
Easy
View Solution$A$ mass spectrometer is a device which selects particles of equal mass. An ion with electric charge $q > 0$ and mass $m$ starts at rest from a source $S$ and is accelerated through a potential difference $V$. It passes through a hole into a region of constant magnetic field $\vec B$ perpendicular to the plane of the paper as shown in the figure. The particle is deflected by the magnetic field and emerges through the bottom hole at a distance $d$ from the top hole. The mass of the particle is:
Difficult
View Solution$A$ long thin-walled pipe of radius $R$ carries a current $I$ along its length. The current density is uniform over the circumference of the pipe. The magnetic field at the center of the pipe due to the quarter portion of the pipe shown is:
Match the following:
List-$I$ List-$II$ $a$. Fleming's left-hand rule $e$. Direction of induced current $b$. Fleming's right-hand rule $f$. South pole $c$. Clockwise current $g$. North pole $d$. Anticlockwise current $h$. Direction of force
The correct answer is:
| List-$I$ | List-$II$ |
| $a$. Fleming's left-hand rule | $e$. Direction of induced current |
| $b$. Fleming's right-hand rule | $f$. South pole |
| $c$. Clockwise current | $g$. North pole |
| $d$. Anticlockwise current | $h$. Direction of force |
The correct answer is:
Vedclass Products
For Students
Vedclass Test Series
Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.
Start Free TrialFor Teachers
Exam Paper Generator
Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.
Try FreeFor Institutes
Online Exam Module
Live online exams with unlimited students, 360° analytics & white-label branding.
See Demo