DC Motors The torque developed by a dc motor is directly proportional to Armature resistance × armature current None of the listed here Armature resistance × applied voltage Flux per pole × armature current Armature resistance × armature current None of the listed here Armature resistance × applied voltage Flux per pole × armature current ANSWER DOWNLOAD EXAMIANS APP
DC Motors If a D.C. motor designed for 40°C ambient temperature is to be used for 50°C ambient temperature, then the motor Of higher H.P. should be selected Of lower H.P. should be selected Is to be de-rated by a factor recommended by manufacturer and select the next higher H.P. motor Can be used for 50°C ambient temperature also Of higher H.P. should be selected Of lower H.P. should be selected Is to be de-rated by a factor recommended by manufacturer and select the next higher H.P. motor Can be used for 50°C ambient temperature also ANSWER DOWNLOAD EXAMIANS APP
DC Motors The commutating winding is basically used in a dc machine To improve commutation None of the listed here To control the speed of machine To reduce armature reaction To improve commutation None of the listed here To control the speed of machine To reduce armature reaction ANSWER DOWNLOAD EXAMIANS APP
DC Motors A dc motor is still used in industrial applications because it Is cheap None of the listed here Provides fine speed control Is simple in construction Is cheap None of the listed here Provides fine speed control Is simple in construction ANSWER DOWNLOAD EXAMIANS APP
DC Motors As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent a heavy current from flowing though the armature circuit Armature is temporarily open circuited A resistance is connected parallel to the armature A high value resistor is connected across the field winding A resistance is connected in series with armature Armature is temporarily open circuited A resistance is connected parallel to the armature A high value resistor is connected across the field winding A resistance is connected in series with armature ANSWER DOWNLOAD EXAMIANS APP
DC Motors The speed of a motor falls from 1100 r.p.m. at no-load to 1050 r.p.m. at rated load. The speed regulation of the motor is 2.22% 4.76% 8.85% 6.77% 2.22% 4.76% 8.85% 6.77% ANSWER DOWNLOAD EXAMIANS APP
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