(a) What would have to be the self-inductance of a solenoid for it to store 10.0J of energy when a 1.50-A current runs throught it?
(b) If this solenoid's cross-sectional diameter is 4.00 cm, and if you could wrap its coils to a density of 10 coils/mm. how long would the solenoid be? (See Exercise 30.11.) Is this a realistic length for ordinary laboratory use?