The figure shows three situations when an electron moves with velocity $\vec v$ travels through a uniform magnetic field $\vec B$. In each case, what is the direction of magnetic force on the electron
  • A$+ve\,\,z-$ axis, $-ve\,\,x-$ axis, $+ve\,\,y-$ axis
  • B$-ve\,\,z-$ axis, $-ve\,\,x-$ axis and zero
  • C$+ve\,\,z-$ axis, $+\,ve\,\,x-$ axis and zero
  • D$-ve\,\,z-$ axis, $+ve\,\,x-$ axis and zero
Medium
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