Electrical Machines Considering a galvanometer is connected to the rotor of a 3 - Φ, 4 pole, 50 Hz IM and is making 130 oscillations in a minute, then calculate the rotor speed? 1440. 1435. 1450. 1500. 1440. 1435. 1450. 1500. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ induction motor power factor at starting is high as compared to that while running. power factor at starting in the same as that while running. power factor at starting is low as compared to that while running. none of them. power factor at starting is high as compared to that while running. power factor at starting in the same as that while running. power factor at starting is low as compared to that while running. none of them. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V dc series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 Ω. The value of resistance which must be added to obtain rated torque at 1000 rpm is 2.2 Ω 1.9 Ω 6 Ω 5.7 Ω 2.2 Ω 1.9 Ω 6 Ω 5.7 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If iron loss and full load copper loss of any transformer are denoted by Pi and Pc, then the load corresponding to maximum efficiency is given by (Pi / Pc) × full Load. (Pi / Pc)0.5 × Full Load. (Pi / Pc)1.6 × full Load. (Pi / Pc)2 × full Load. (Pi / Pc) × full Load. (Pi / Pc)0.5 × Full Load. (Pi / Pc)1.6 × full Load. (Pi / Pc)2 × full Load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines 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 motor is 2.56 %. 2.57 %. 4.76%. 3.76%. 2.56 %. 2.57 %. 4.76%. 3.76%. 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 must be replaced field winding must be excited by low voltage dc supply the field winding connection must be reversed the armature connection must be reversed the field winding must be replaced field winding must be excited by low voltage dc supply the field winding connection must be reversed ANSWER DOWNLOAD EXAMIANS APP