A straight conductor carries a current. Assume that all free electrons in the conductor move with the same drift velocity $v$ . A and B are two observers on a straight line XY parallel to the conductor. A is stationary. B moves along XY with a velocity $v$ in the direction of the free electrons :

A and B observe the same magnetic field

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A observes a magnetic field, B does not

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A and B observe magnetic fields of the same magnitude but opposite directions

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A and B do not observe any electric field

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Solution

The correct option is B A observes a magnetic field, B does not
Since B is in motion with respect to the charge so he can not see any magnetic field but A will see that.

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A straight conductor carries a current. Assume that all free electrons in the conductor move with the same drift velocity v. A and B are two observers on a straight line XY parallel to the conductor. A is stationary. B moves along XY with a velocity v in the direction of the free electrons :

The correct option is B A observes a magnetic field, B does notSince B is in motion with respect to the charge so he can not see any magnetic field but A will see that.

A straight conductor carries a current. Assume that all free electrons in the conductor move with the same drift velocity $v$ . A and B are two observers on a straight line XY parallel to the conductor. A is stationary. B moves along XY with a velocity $v$ in the direction of the free electrons :

The correct option is B A observes a magnetic field, B does not
Since B is in motion with respect to the charge so he can not see any magnetic field but A will see that.