Electrical Machines For a DC machine having P no of pole pairs Z no of conductors having length L of resistivity ρ and cross section S are arranged. what is the armature resistance for lap-winding ? PZL/4Sa² PZL/4SP² PZL/4S PZL/ 4Sa PZL/4Sa² PZL/4SP² PZL/4S PZL/ 4Sa ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increases in field excitation of a DC generator, its generated emf increases upto a limit and then remains almost constant. decreases. increases. remains constant. increases upto a limit and then remains almost constant. decreases. increases. remains constant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The 3 - Φ induction motor with rotor circuit open will make noise. get over heated. run normally. not run. make noise. get over heated. run normally. not run. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4 1, 2, 3 2, 3 ,5 2, 3, 4, 5 2, 3, 4 1, 2, 3 2, 3 ,5 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Shunt Motor the speed can be increased by Increasing the field current. Increasing the armature current. Increasing the field current. Decreasing the field current. Increasing the field current. Increasing the armature current. Increasing the field current. Decreasing the field current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the field winding connection must be reversed the field winding must be replaced the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding connection must be reversed the field winding must be replaced the armature connection must be reversed field winding must be excited by low voltage dc supply ANSWER DOWNLOAD EXAMIANS APP