A long solenoid carrying a current produces a magnetic field B along i – McqOptions

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1.	A long solenoid carrying a current produces a magnetic field B along its axis. If the current is doubled and the number of turns per cm is halved, the new value of the magnetic field is [CBSE PMT 2003]
A.	B
B.	2 B
C.	4 B
D.	B/2
Answer» B. 2 B

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