MCQ
If cathode rays are projected at right angles to a magnetic field, their trajectory is
- AEllipse
- ✓Circle
- CParabola
- DNone of these
✓
Answer
Correct option: B.
Circle
b
Let the magnetic field be along North direction. Let cathode ray pass perpendicular to the magnetic field towards east.then it gets deflected downwards.
Let the magnetic field be along North direction. Let cathode ray pass perpendicular to the magnetic field towards east.then it gets deflected downwards.
Fleming's left hand rule is meant for the movement of positively charged particles.
But cathode rays are stream of negatively charged electrons. So opposite to the previous one. And like postive charge it will make a circular trajectory.
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