Electrical Machines What is the mechanical power developed by a DC series motor is maximum? Back emf is equal to half the applied voltage. Back emf is equal to zero. None of above. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. Back emf is equal to zero. None of above. Back emf is equal to applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Capacitor fitted with ceiling / table fans is of the value of 2 - 3 µF. 0.1 µF. 1 - 2 µF. 5 - 10 F. 2 - 3 µF. 0.1 µF. 1 - 2 µF. 5 - 10 F. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hopkinson test is conducted under which of the following condition? no load half load any of the above full load no load half load any of the above full load ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC motor is laminated to reduce the mass. to reduce the hysteresis loss. to reduce the eddy current loss. to reduce the inductor. to reduce the mass. to reduce the hysteresis loss. to reduce the eddy current loss. to reduce the inductor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by Nr = 120f / p × (1-s). Ns = 120f /p × ( 1 - r). None of these Ns = 120f / p × ( 1 - s ). Nr = 120f / p × (1-s). Ns = 120f /p × ( 1 - r). None of these Ns = 120f / p × ( 1 - s ). 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, 250 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 2166.67V, 230 rpm. 541.67V, 250 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 2166.67V, 230 rpm. ANSWER DOWNLOAD EXAMIANS APP