question

the energy stored in a solenoid of inductance l is u. the number of turns per unit length of the solenoid is doubled. keeping the current and all other factors same, find (a) change in inductance of the solenoid, and (b) the final energy stored in the inductor.

 

 

 

 

 

 

a)

when n is doubled l also doubles

b)

since inductance l doubles the energy e also doubles