Electrical Machines Find the developed torque DC Series Motor having armature resistance of 0.2 Ω and taking armature current of 60 A is connected to 250 V supply. Considered brush drop of 1 V each. 133.22 N-m cant be determined. 234.76 N-m. 266.20 N-m. 133.22 N-m cant be determined. 234.76 N-m. 266.20 N-m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? 120P / N Hz. 120 / PN Hz. PN / 2 Hz. 120N / P Hz. 120P / N Hz. 120 / PN Hz. PN / 2 Hz. 120N / P Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous machine has P number of poles, find the relation between electrical angular momentum (ωe) and mechanical angular momentum (ωm)? ωe = P*ωm ωe = ωm ωe = 2/P*ωm ωe = P/2*ωm ωe = P*ωm ωe = ωm ωe = 2/P*ωm ωe = P/2*ωm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a DC cummulative compound wound motor is loaded Torque decrease and speed increases. Torque increase and speed decrease. Both torque and speed decrease. Torque and speed both increase. Torque decrease and speed increases. Torque increase and speed decrease. Both torque and speed decrease. Torque and speed both increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Copper brushes in DC machine are used None of these where high voltage and low current. where low voltage and high currents are involved. in both of above cases. None of these where high voltage and low current. where low voltage and high currents are involved. in both of above cases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the armature connection must be reversed the field winding connection must be reversed field winding must be excited by low voltage dc supply the field winding must be replaced the armature connection must be reversed the field winding connection must be reversed field winding must be excited by low voltage dc supply the field winding must be replaced ANSWER DOWNLOAD EXAMIANS APP