Which of the following is an accurate statement A Magnetic f

Which of the following is an accurate statement? A) Magnetic field lines have as their sources north and south poles. B) A current carrying loop of wire tends to line up with its plane parallel to an external magnetic tends to line up with its plane paralle to an external magnetic field in which it is positioned C) The magnetic force on a current carrying wire is greatest when the wire is parallel to the magnetic field. D) The magnetic force on a moving charge does not change its energy. E) A magnetic field line is, by definition, tangent to the direction of the magnetic force on a moving charge at a given point in space.

Solution

Answeres are A ,D E

Because magnetic field exerts forces on magnetic poles.

The tangent to a field line is in the direction of the magnetic field

Magnetic force on moving charge at constant speed is

                 F = B ( v x q )