The magnetic intensity at the centre of a long current carrying...

The magnetic intensity $H$ is defined as the product of the number of turns per unit length in a coil $n$ and the current that it carries$I$.

The magnetic field of a solenoid is given by $B = {\mu}_{0}ni$

$H = \dfrac{B}{{\mu}_{0}} = \dfrac{{\mu}_{0}ni}{{\mu}_{0}} ⇒ H = ni . . . ( i )$

The given data is

$H = 1 . 6 \times {10}^{3}A{m}^{- 1}$

$n = 8$ per $cm$

Substituting the values in equation (i)

$⇒ 1 . 6 \times 1000 = \dfrac{8}{\dfrac{1}{100}} \times i$

$⇒ i = 2A$