An electron revolves around the nucleus in a circular path with angular momentum $\vec{L}$. $A$ uniform magnetic field $\vec{B}$ is applied perpendicular to the plane of its orbit. If the electron experiences a torque $\vec{\tau}$,then

  • A
    $\vec{\tau} \parallel \vec{L}$
  • B
    $\vec{\tau}$ is anti-parallel to $\vec{L}$
  • C
    $\vec{\tau} \cdot \vec{L} = 0$
  • D
    Angle between $\vec{\tau}$ and $\vec{L}$ is $45^{\circ}$

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