Question

Pick the correct options.

• A. Magnetic field is produced by charged particle without acceleration
• B. Magnetic poles are only mathematical assumptions having no real existence
• C. A north pole is equivalent to a clockwise current and a south pole are equivalent to an anticlockwise current
• D. A bar magnet is equivalent to a long, straight current

Answer 1

Answer: (A), (B)

The correct options are
A Magnetic field is produced by charged particle without acceleration
B Magnetic poles are only mathematical assumptions having no real existence

Moving electric charges produce magnetic fields. Hence option A is correct.

Magnetic poles are mathematical assumptions only. There are actually no north or south poles, they are mere conventions.

A north pole is equivalent to anticlockwise current and south pole the opposite.

A long straight current has cylindrical magnetic fields around. However fields around bar magnet form closed loops passing through the inside of the magnet.