. What is the magnitude of the field 
at a point 
from the wire?. What is the magnitude of the field at a point from the wire?Ans: We are given the following:
Current in the wire, 
Distance of a point from the wire, 
Magnitude of the magnetic field at this point could be given as:
![\[\begin{array}{l} \mathrm{B}=\frac{\mu_{0}}{4 \pi} \frac{21}{r} \\ \text { Where, } \mu_{0}=\text { Permeability of free space }=4 \pi \times 10^{-7} \mathrm{~T} \mathrm{~m} \mathrm{~A}^{-1} \\ \Rightarrow \mathrm{B}=\frac{4 \pi \times 10^{-7} \times 2 \times 35}{4 \pi \times 0.2} \\ \Rightarrow \mathrm{B}=3.5 \times 10^{-5} \mathrm{~T} \end{array}\]](https://www.learnatnoon.com/s/wp-content/ql-cache/quicklatex.com-6bca16122dfc6df6571db97ac5d002f0_l3.png "Rendered by QuickLaTeX.com")
Hence, the magnitude of the magnetic field at a point from the wire is found to be 
.
.
)
west of the geographic north. The north tip of the magnetic needle of a dip circle placed in the plane of magnetic meridian points above the horizontal. The horizontal component of the earth’s field is measured to be 
Specify the direction and magnitude of the earth’s field at the location.At a certain location in Africa, a compass points west of the geographic north. The north tip of the magnetic needle of a dip circle placed in the plane of magnetic meridian points above the horizontal. The horizontal component of the earth’s field is measured to be Specify the direction and magnitude of the earth’s field at the location.
and 
carrying currents of 
and 
in the same direction are separated by a distance of 
. Estimate the force on a 
section of wire A.
wire carrying a current of 
is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 
. What is the magnetic force on the wire?
and making an angle of 
with the direction of a uniform magnetic field of 
-turns carrying current 
.. An electron moving at 
is at distance 
from the wire. Find the force acting on the electron if its velocity is directed towards the wire.