An ideal solenoid, of radius R and n turns per unit length, has
a current flowing through it. The current, I, varies with time, t,
according to I = I0 + at where I0 and a are constants. A conducting
ring of radius, r, is placed inside the solenoid with its axis
coinciding with the axis of the solenoid. The ring has a resistance
per unit length of H (in units of Ω/m).
(a) Use Lenz’s law to determine the...