question_answer

A negative test charge is moving near a long straight wire carrying a current. The force acting on the test charge is parallel to the direction of the current. The motion of the charge is -       [JEE Online 09-04-2017]

A)  away from the wire

B)  towards the wire

C)  parallel to the wire along the current

D)  parallel to the wire opposite to the current

Correct Answer: B

Solution :

  \[\vec{F}=q(\vec{v}\times \vec{B})\]