5 DC Motors
DC motors convert electrical energy into mechanical energy and have construction very similar to that of a DC generator. Generators are operated in protected locations. Therefore, their construction is usually of the open type. Since DC motors do not operate in protected locations, they face dust, moisture, fumes and tend to get mechanical damage. Hence, their construction is of closed type. The operation of motors is based on the principle – when a current-carrying conductor is placed in a magnetic field, it experiences a mechanical force. The magnitude of this force is F = BIL, and its direction is determined by Fleming's left-hand rule. The aim ...
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