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Question
Study the following principle and answer the question.
A force is excreted on the current carrying conductor. The direction of this force depends on both the direction of the current and the direction of the magnetic field. This force is maximum when the direction of current is perpendicular to the direction of the magnetic field.
a) By which law we can determine the direction of force excreted on the current carrying conductor.
b) In which electrical equipment this principle is used.
c) Draw a diagram representing construction of this equipment.
d) Write the working of this equipment in brief.
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Solution
a. Fleming’s left hand rule
b. Electric motor
d. completed, the current flows through the coil in the direction A-B-C-D.
ii. The coil is in the magnetic field therefor according to Fleming’s left hand rule force exerted on the AB branch is in downward direction and on the CD branch it is in upward direction.
iii. After half rotation current in the coil start flowing through D-C-B-A direction.
iv. therefore, on DC branch force is in downward direction and BA branch it is in upward direction so its complete remaining half rotation.
In this way after every half rotation the direction of the current in the coil changes and coil continue to rotate.
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