Problem $7$: $(11\%$ of Assignment Value$)$

A uniform magnetic field with a magnitude of $38\mathrm{.}4$ mT completely fills a cylindrical volume of space with a length of $27\mathrm{.}1$ cm and a radius of $1\mathrm{.}37$ cm $.$

Part $($a$)$

How much energy, in millijoules, is stored in the magnetic field in the given volume of space?

U$\_($M$)=$

mJ

Part $($b$)$

Suppose the cylindrical volume is the interior of an air$-$filled solenoid with an inductance of $345$ muH. What is the current, in amperes, in the wire windings of the

solenoid?