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Identify the correct statement about the magnetic field lines.( )
A. These start always from closed loops
B. These lines always form closed loops 
C. Both A and B are correct
D. Both A and B are wrong

Answer

B
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Solution

Solution for Identify the correct statement about the magnetic field lines.(   )A. These start always from closed loopsB. These lines always form closed loops C. Both A and B are correctD. Both A and B are wrong
Magnetic field lines always form closed loops.But they do not start from closed loops.Example, in bar magnet they start from north pole outside the magnet and terminate at south pole.
So, option B is correct.
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