Question

In a solenoid of $0.5m$ long the wires are wounded around. In every layer the number of turns is $500$. If its radius is $1.4cm$ and $5A$ current is flowing in it, then calculate the value of magnetic field at its centre.

Answer 1

Length of solenoi $I=0.5m$
Number of turns $N=2\times 500=1000$
Flowing current $I=5A$
Magnetic field produced at centre
$B={\mu }_0\frac{N}{l}I$
$B=4\pi \times {10}^{-7}\times \frac{100}{0.5}\times 5$
$B=4\times 3.14\times {10}^{-7}\times {10}^4$
$B=12.56\times {10}^{-3}T$