$A$ long solenoid has $n$ turns per meter and current $I \ A$ is flowing through it. The magnetic field at the ends of the solenoid is

If a copper rod carries a direct current,the magnetic field associated with the current will be

$A$ current $I$ flows along the length of an infinitely long,straight and thin-walled pipe. Then

$A$ long solenoid is formed by winding $70$ turns $cm^{-1}$. If $2.0\,A$ current flows,then the magnetic field produced inside the solenoid is $.......\times 10^{-4}\,T$ $\left(\mu_0 = 4\pi \times 10^{-7}\,TmA^{-1}\right)$

If the magnetic field inside a solenoid is $B$,then the magnetic energy stored in it per unit volume is (where $c$ is the speed of light in vacuum and $\varepsilon_0$ is the permittivity of free space).

$A$ long copper tube of inner radius $R$ carries a current $i$. The magnetic field $B$ inside the tube is