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Question
A vertical wire carries a current in upward direction. An electron beam sent horizontally towards the wire will be deflected
Options
towards right
towards left
upwards
downwards.
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Solution
upwards
A vertical wire is carrying current in upward direction, so the magnetic field produced will be anticlockwise (according to the right-hand thumb rule). As the electron beam is sent horizontally towards the wire, the direction of the current will be horizontally away from the wire (direction of conventional current is opposite to the direction of the negative charge). According to Fleming's left-hand rule, the force will act in upward direction, deflecting the beam in the same direction.
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