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Question
State the factors, on which depends the magnitude of the force acting on current carrying conductor, when it is kept in a magnetic field perpendicular to it.
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Solution
Experimentally it is found that the magnitude of the force acting on a current-carrying conductor kept in a magnetic field in a direction perpendicular to it, depends on the following factors:
(i) The F is directly proportional to the length of the current-carrying conductor, i.e., F ∝ l.
(ii) F is directly proportional to the strength of the magnetic field, i.e., F ∝ B.
(iii) F is directly proportional to the strength of the current flowing in the conductor, i.e., F ∝ i.
Combining the above factors we find that:
or F ∝ i Bl
F = KiBl
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