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Question
Cathode rays are passing through a discharge tube. In the tube, there is ______________ .
Options
an electric field but no magnetic field
a magnetic field but no electric field
an electric as well as a magnetic field
neither an electric nor a magnetic field
Solution
an electric as well as a magnetic field
Cathode rays consist of beams of electrons that constitute current and, hence, magnetic field. We know electric field is produced by a charge, whether it is stationary or moving, So, electric field will also be present inside the tube.
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