Write the equation for the magnetic field at an inside point of a very long solenoid.

(N/A) For a very long solenoid (ideal solenoid) carrying a current $I$ with $n$ turns per unit length,the magnetic field $B$ at an inside point is given by the formula:
$B = \mu_0 n I$
where:
$B$ is the magnetic field strength in Tesla $(T)$,
$\mu_0$ is the permeability of free space $(4\pi \times 10^{-7} \ T \cdot m/A)$,
$n$ is the number of turns per unit length $(N/L)$,
$I$ is the current flowing through the solenoid in Amperes $(A)$.