Electrical Machines The mechanical power is developed by a DC motor is maximum when back emf is equal to twice of applied voltage. none of above. back emf is equal to applied voltage. back emf is equal to half of applied voltage. back emf is equal to twice of applied voltage. none of above. back emf is equal to applied voltage. back emf is equal to half of applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is not a necessary condition to be satisfied for synchronising an incoming alternator to an already operating alternator? same prime mover speed same frequency same voltage magnitude same phase sequence same prime mover speed same frequency same voltage magnitude same phase sequence ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running with a divertor connected across its field winding. If the divertor resistance is reduced then the speed of the motor will remain unaltered. increase. become execessively high. decrease. remain unaltered. increase. become execessively high. decrease. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When two DC series motors are connected in parallel, the resultant speed is zero. more than normal speed. normal speed. less than normal speed. zero. more than normal speed. normal speed. less than normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC cumulatively compounded motor delivers rated load torque at rated speed. If the series field is short-circuited, then the armature current and speed will increase and decrease respectively both increase decrease and increase respectively both decrease increase and decrease respectively both increase decrease and increase respectively both decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous motor is supplying a load at unity power factor. If the load on the motor is increased keeping its excitation and terminal voltage constant, the power factor will become lagging None of these will remain the same will become leading will become lagging None of these will remain the same will become leading ANSWER DOWNLOAD EXAMIANS APP