All Free Electrical Engineering MCQs with Answers

• A. final control element
• B. amplifier
• C. comparator
• D. sensor
• E. none of the above

Explanation: The controller processes the error signal and sends its corrective command to the final control element, such as a valve, motor, or…

• A. Underdamping
• B. Overdamping
• C. Poor stability at reduced values of open loop gain
• D. Low-level oscillations

Explanation: Backlash introduces a dead zone and can produce small sustained oscillations or limit cycles even when the linear control system is…

• A. sensor
• B. clipper
• C. comparator
• D. amplifier

Explanation: A controller fundamentally compares the desired value with the feedback value to form an error signal, then uses that error to regulate…

• A. All the co-efficients can have zero value
• B. All the co-efficients are always non-zero
• C. Only one of the static error co-efficients has a finite non-zero value
• D. None of the above

Explanation: For a conventional system classified by type, the position, velocity, and acceleration error constants do not all have finite non-zero…

• A. The system is relatively stable
• B. The system is highly stable
• C. The system is highly oscillatory
• D. None of the above

Explanation: A gain margin near unity, or a phase margin near zero, places the system close to the stability limit.

• A. The time constant of the system
• B. Damping of the system
• C. The gain of the system
• D. The time constant and suppress the oscillations
• E. None of the above

Explanation: Acceleration or second-derivative feedback changes the effective time constant and can improve damping, thereby suppressing oscillations.

• A. oscillations
• B. step input
• C. negative sign
• D. positive sign

Explanation: Regenerative feedback feeds the returned signal in phase with the input, so it is positive feedback.

• A. saturation in amplifying stages
• B. loss of gain
• C. vibrations
• D. oscillations

Explanation: Excessive noise can drive amplifier stages beyond their permissible signal range, causing saturation.

• A. The order of the system
• B. The time constant
• C. The output for any given input
• D. The steady state gain

Explanation: Once the transfer function is known, the output is obtained from Y(s) = G(s)X(s) for any specified input, subject to zero initial…

• A. Band width
• B. Overall gain
• C. Distortion
• D. Instability

Explanation: Negative feedback reduces overall gain, distortion, and sensitivity to parameter changes, while improving stability and increasing…

• A. Ward Leonard control
• B. Field controlled D.C. motor
• C. Stroboscope
• D. Metadyne

Explanation: A field-controlled DC motor can operate as an open-loop system when its speed is controlled by changing field current without measuring…

• A. remains unaffected
• B. decreases by the same amount as the gain increase
• C. increases by the sane saaaajajt as the gain decrease
• D. decreases by the same amount as the gain decrease

Explanation: For a feedback amplifier, negative feedback lowers gain while extending bandwidth approximately by the same factor.

• A. Brain
• B. Hands
• C. Legs
• D. Eyes

Explanation: The eyes sense the path and detect positional error, the brain processes it, and the legs provide the corrective action.

• A. Auto-pilot for an aircraft
• B. Direct current generator
• C. Car starter
• D. Electric switch

Explanation: An aircraft autopilot measures the aircraft response and feeds corrective information back to the controller, making it a closed-loop…

• A. Servomechanism
• B. Feedback
• C. Output pattern
• D. Input pattern

Explanation: Feedback returns a portion of the output to the input for comparison and correction, which is the defining feature of a closed-loop…

• A. open
• B. closed
• C. partially closed
• D. any of the above

Explanation: A conventional automatic toaster operates for a preset time and then switches off, without measuring the browning of the toast.

• A. Less expensive
• B. Recalibration is not required for maintaining the required quality of the output
• C. Construction is simple and maintenance easy
• D. Errors are caused by disturbances

Explanation: Open-loop systems cannot automatically correct changes in plant characteristics or operating conditions, so periodic recalibration may be…

• A. Digestive system
• B. Perspiration system
• C. Ear
• D. Leg movement

Explanation: Perspiration helps regulate body temperature by allowing evaporative cooling when the body becomes too warm.

• A. computer control system
• B. digital data system
• C. stochastic control system
• D. adaptive control system

Explanation: A stochastic control system is designed or analyzed when the system or its inputs include random, probabilistic actions.

• A. Clutch
• B. Eyes
• C. Needle of the speedometer
• D. Steering wheel
• E. None of the above

Explanation: The speedometer needle shows the car’s actual speed, providing the driver with feedback to compare with the desired 50 km/h.