Question

A solenoid with 1000 turns has a cross-sectional area of 7.0 cm2 and length of 25 cm. How much energy is stored in the magnetic field of the solenoid when it carries a current of 10.0 a?

Answer 1

Answer:

The energy stored in the solenoid is 0.18J

Explanation:

We need to obtain the inductance in order to calculate the energy:

$L=\µ_o*N^2*\frac{A}{L}\\\\L=4*\pi*10^{-7}*1000^2*\frac{(7.0*10^{-4}m^2)}{25*10^{-2}m}\\L=3.51mH$

The energy stored in the solenoid is given by:

$U_g=\frac{1}{2}*L*i^2\\\\U_g=\frac{1}{2}*3.51*10^{-3}*10.0^2\\\\U_g=0.18J$