Question
A current of 1.0A is established in a tightly wound solenoid of radius 2cm having 1000 turns/ metre. Find the magnetic energy stored in each metre of the solenoid.
✓
Answer
i = 1.0A, r = 2cm, n = 1000 turn/m Magnetic energy stored $=\frac{\text{B}^2\text{V}}{2\mu_0}$ Where B → Magnetic field, V → Volume of Solenoid.$=\frac{\mu_0\text{n}^2\text{i}^2}{2\mu_0}\times\pi\text{r}^2\text{h}$
$=\frac{4\pi\times10^{-7}\times10^6\times1\times\pi\times4\times10^{-4}\times1}{2} \ [\text{h}=1\text{m}]$
$=8\pi\times10^{-5}$
$78.956\times10^{-5}=7.9\times10^{-4}\text{J}$.
$=\frac{4\pi\times10^{-7}\times10^6\times1\times\pi\times4\times10^{-4}\times1}{2} \ [\text{h}=1\text{m}]$
$=8\pi\times10^{-5}$
$78.956\times10^{-5}=7.9\times10^{-4}\text{J}$.
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