The following statement is false for Helmholtz coils
in Helmholtz coils, both coils are coaxial
planes of Helmholtz coils are perpendicular to each other.
The distance between coils is equal to the radius of either coil.
The magnetic field produced at the central part between the coils is uniform.
Figure shows a square loop $ABCD$ with edge length $a$. The resistance of the wire $ABC$ is $r$ and that of $ADC$ is $2r$. The value of magnetic field at the centre of the loop assuming uniform wire is
A Rowland ring of mean radius $15\; cm\;3500$ turns of wire wound on a ferromagnetic core of relative permeability $800.$ What is the magnetic field $B$ (in $T$) in the core for a magnetizing current of $1.2\; A?$
A coil carrying a heavy current and having large number of turns mounted in a $N-S$ vertical plane and $a$ current flows in clockwise direction. A small magnetic needle at its cente will have its north pole in
The unit vectors $\hat i,\;\hat j\;{\rm{and }}\,\hat k$ are as shown below. What will be the magnetic field at $O$ in the following figure
As shown in the figure, two infinitely long, identical wires are bent by $90^o$ and placed in such a way that the segments $LP$ and $QM$ are along the $x-$ axis, while segments $PS$ and $QN$ are parallel to the $y-$ axis. If $OP = OQ = 4\, cm$, and the magnitude of the magnetic field at $O$ is $10^{-4}\, T$, and the two wires carry equal current (see figure), the magnitude of the current in each wire and the direction of the magnetic field at $O$ will be $(\mu_ 0 = 4\pi \times10^{-7}\, NA^{-2})$