Question 124 of 311

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:

AAway from the wireBTowards the wireCParallel to the wire along the currentDParallel to the wire opposite to the current

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Answer: (B) Towards the wire

Force on a moving charge, $\vec{F}=q\left(\vec{v}\times \vec{B}\right)$

Here, $∵q=-ve$

$\Rightarrow \vec{F}=-q\left(\vec{v}\times \vec{B}\right)$

$∴\text{motion of}-q\text{is towards the wire.}$

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