A solenoid has n turns and length l. If length is reduced to l/2 and turns are doubled then magnetic field B produced by it becomes equal to a) 2B b) 4B c) 1/2 B d) None of these

A solenoid has n turns and length l. If length is reduced to l/2 and turns are doubled then magnetic field
B produced by it becomes equal to
a) 2B b) 4B c) 1/2 B d) None of these
by

1 Answer

Answer :

a) 2B
by

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