Electrical Machines To control the speed of an induction motor, the supply frequency is reduced by 10%. For the same magnetizing current to remain constant, the supply voltage must be increased by 10% reduced by 20% increased by 20% reduced by 10% increased by 10% reduced by 20% increased by 20% reduced by 10% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 541.67V, 200 rpm. 2166.67V, 230 rpm. 2166.67V, 270 rpm. 541.67V, 250 rpm. 541.67V, 200 rpm. 2166.67V, 230 rpm. 2166.67V, 270 rpm. 541.67V, 250 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by changing the load. varying the applied voltage. changing the field excitation. varying the speed. changing the load. varying the applied voltage. changing the field excitation. varying the speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The polarity of a DC generator can be reversed by any of above. increasing field current. reversing the field current. reversing field electric current as well as direction of rotation. any of above. increasing field current. reversing the field current. reversing field electric current as well as direction of rotation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a single phase induction motor, the starting torque developed is proportional to 1/V supply voltage V 1/V² V² 1/V supply voltage V 1/V² V² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the source voltage of a DC motor is increased, which of the following will decrease? Starting torque, operating speed, full load current. Operating speed. Full load current. Starting torque. Starting torque, operating speed, full load current. Operating speed. Full load current. Starting torque. ANSWER DOWNLOAD EXAMIANS APP
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