Electrical Engg (EEE) - MCQ Practice Questions

A 3-phase, 50 Hz, 4-pole synchronous motor operates at rated speed. The excitation is reduced by 20%. What happens?

In a synchronous generator connected to an infinite bus, if the excitation is increased beyond rated value:

In a synchronous generator, the voltage regulation is negative when:

For a 3-phase synchronous motor connected to infinite bus, increasing field excitation beyond the critical value will:

The cogging torque in a DC motor is primarily due to:

A 3-phase induction motor develops maximum torque at a slip of 0.4. The motor is operating at slip 0.1. What is the ratio of starting torque to running torque?

A synchronous generator operating at leading power factor supplies current to an infinite bus. This condition represents:

The crawling phenomenon in induction motors occurs due to:

A synchronous motor is running at no-load with normal excitation. If excitation is increased, the armature current will:

The phenomenon of cogging in induction motors occurs due to:

The double-field revolving theory is used to analyze:

If the frequency of supply to an induction motor is reduced while maintaining the same voltage, the motor torque will:

In a DC series motor, the back EMF at rated load is 200V when the supply voltage is 230V. If the motor is suddenly unloaded, which of the following will occur?

The swing equation of a synchronous machine is given by: 2H(d²δ/dt²) = Pm - Pe - D(dδ/dt). What does H represent?

The critical clearing angle (δcr) in transient stability analysis represents:

The fault level (short-circuit capacity) at a bus is determined by:

The maximum power transfer in an AC transmission system occurs when the sending and receiving end voltages are:

For a system with open-loop transfer function G(s)H(s) = K/[s(s+1)(s+2)], the number of asymptotes in root locus is:

A proportional-integral (PI) controller transfer function is Gc(s) = Kp + Ki/s. Its effect is:

The centroid of asymptotes in root locus is located at: