Engine 2014: Electricity

1. A as the motor approaches synchronous speed the voltage induced across the rotor winding decays in amplitude and frequency causing the polarized frequency relay to drop out which energizes the field contactor, thus connecting the DC field across the field winding
2. B as the motor approaches synchronous speed the voltage induced across the rotor winding increases in amplitude and frequency causing the polarized frequency relay to pick up which de- energizes the field contactor, thus disconnecting the DC field across the field winding
3. C as the motor approaches synchronous speed the voltage induced across the rotor winding decays in amplitude and frequency causing the polarized frequency relay to pick up which de- energizes the field contactor, thus disconnecting the DC field across the field winding
4. D as the motor approaches synchronous speed the voltage induced across the rotor winding increases in amplitude and frequency causing the polarized frequency relay to drop out which energizes the field contactor, thus connecting the DC field across the field winding

Tip: press A-D to answer