Actuator types and applications – MCQs – EE

1. What is the main function of an actuator in a control system?
(A) To sense environmental changes
(B) To convert electrical signals into physical motion
(C) To store energy
(D) To filter signals

2. Which of the following is an example of an electrical actuator?
(A) Solenoid
(B) Pneumatic cylinder
(C) Hydraulic piston
(D) Thermal relay

3. An actuator converts:
(A) Mechanical energy to electrical energy
(B) Electrical energy to mechanical energy
(C) Chemical energy to thermal energy
(D) Magnetic energy to electrical energy

4. Which of the following is a rotary actuator?
(A) DC motor
(B) Solenoid
(C) Linear piston
(D) Pneumatic cylinder

5. Which type of actuator uses compressed air as its power source?
(A) Hydraulic actuator
(B) Pneumatic actuator
(C) Electrical actuator
(D) Magnetic actuator

6. Which actuator is suitable for high force and heavy load applications?
(A) Electric actuator
(B) Pneumatic actuator
(C) Hydraulic actuator
(D) Thermal actuator

7. The main advantage of pneumatic actuators is:
(A) Clean and fast operation
(B) High precision
(C) High energy efficiency
(D) No maintenance

8. Hydraulic actuators operate using:
(A) Compressed air
(B) Electric current
(C) Pressurized oil or fluid
(D) Steam

9. Which actuator is most commonly used in robotic arms for movement control?
(A) Stepper motor
(B) Pneumatic cylinder
(C) Hydraulic pump
(D) Solenoid valve

10. Solenoid actuators work on the principle of:
(A) Electromagnetic induction
(B) Piezoelectric effect
(C) Thermal expansion
(D) Fluid pressure

11. Which type of actuator provides precise angular control?
(A) Servo motor
(B) Hydraulic actuator
(C) Pneumatic cylinder
(D) Solenoid

12. Linear actuators are used to produce:
(A) Rotary motion
(B) Linear motion
(C) Oscillatory motion
(D) Vibratory motion

13. Stepper motors are often used when:
(A) Continuous rotation is needed
(B) Precise position control is required
(C) High torque is required
(D) Random movement is needed

14. The piezoelectric actuator works on:
(A) Change in shape due to electric field
(B) Change in temperature
(C) Fluid compression
(D) Magnetic flux changes

15. Which actuator is most suitable for micro-positioning applications?
(A) Piezoelectric actuator
(B) Hydraulic actuator
(C) Pneumatic actuator
(D) DC motor

16. The response time of pneumatic actuators is:
(A) Slow
(B) Moderate
(C) Fast
(D) Variable

17. Hydraulic actuators are commonly used in:
(A) Aircraft landing gear systems
(B) Small robotic systems
(C) Electronic circuits
(D) Signal processing

18. Thermal actuators operate on the principle of:
(A) Expansion of materials with temperature
(B) Magnetic attraction
(C) Electric field strength
(D) Air compression

19. The output torque of a DC motor actuator depends on:
(A) Armature current and magnetic field strength
(B) Supply voltage only
(C) Resistance of the winding only
(D) Load inertia only

20. In servo actuators, feedback is used to:
(A) Maintain position accuracy
(B) Reduce mechanical noise
(C) Increase motor speed
(D) Control temperature

21. Electro-hydraulic actuators combine:
(A) Electrical and hydraulic energy
(B) Thermal and magnetic energy
(C) Air and mechanical systems
(D) Digital and analog systems

22. Which actuator is used in automatic door systems?
(A) Pneumatic actuator
(B) DC motor
(C) Hydraulic actuator
(D) Stepper motor

23. In robotics, actuators are used to:
(A) Move joints and links
(B) Process sensor data
(C) Transmit wireless signals
(D) Control logic circuits

24. Electromagnetic actuators convert:
(A) Electrical energy to magnetic force
(B) Magnetic energy to mechanical motion
(C) Both (A) and (B)
(D) Thermal energy to motion

25. The main drawback of hydraulic actuators is:
(A) Oil leakage and maintenance issues
(B) High noise level
(C) Low power density
(D) Limited range of motion

26. Voice coil actuators are typically used in:
(A) Hard disk drives and precision control devices
(B) Hydraulic brakes
(C) Power distribution systems
(D) Solar panels

27. Electrostatic actuators are most suitable for:
(A) MEMS applications
(B) High-power control systems
(C) Hydraulic control valves
(D) Industrial robots

28. Actuator bandwidth refers to:
(A) The speed at which the actuator can respond to input changes
(B) The power output of the actuator
(C) The size of the actuator
(D) The input voltage range

29. Smart actuators are characterized by:
(A) Embedded sensors and control electronics
(B) High inertia
(C) Manual control
(D) Low integration level

30. The main purpose of actuators in mechatronic systems is to:
(A) Execute mechanical actions as commanded by control systems
(B) Collect data from the environment
(C) Filter electrical signals
(D) Store system energy