MEMS and NEMS-based sensors – MCQs – EE

1. What does MEMS stand for?
(A) Micro Electro Mechanical Systems
(B) Micro Electronic Measurement System
(C) Mechanical Energy Monitoring System
(D) Magnetic Electrical Measurement Setup

2. What does NEMS stand for?
(A) Nano Electro Mechanical Systems
(B) Nano Electrical Measurement Setup
(C) New Electronic Mechanical Sensor
(D) Nano Energy Management System

3. MEMS technology integrates mechanical elements with:
(A) Microelectronics
(B) Fluid circuits
(C) Magnetic cores
(D) Optical fibers

4. The typical size range of MEMS devices is:
(A) 1 micrometer to a few millimeters
(B) 1 nanometer to 10 nanometers
(C) 10 centimeters to 1 meter
(D) 1 meter to 10 meters

5. NEMS are primarily an extension of MEMS into which scale?
(A) Nanometer scale
(B) Millimeter scale
(C) Centimeter scale
(D) Kilometer scale

6. MEMS sensors are commonly fabricated using:
(A) Silicon micromachining techniques
(B) Plastic molding
(C) Metal forging
(D) 3D printing only

7. The most common transduction mechanism in MEMS sensors is:
(A) Capacitive or piezoresistive
(B) Magnetic
(C) Optical
(D) Pneumatic

8. A MEMS accelerometer measures:
(A) Acceleration or tilt
(B) Magnetic field
(C) Light intensity
(D) Air pressure

9. MEMS gyroscopes are primarily used to measure:
(A) Angular velocity
(B) Linear speed
(C) Magnetic flux
(D) Temperature

10. The piezoresistive effect in MEMS sensors means:
(A) Resistance changes with applied mechanical stress
(B) Capacitance changes with distance
(C) Voltage changes with temperature
(D) Magnetic field varies with voltage

11. Capacitive MEMS sensors work based on:
(A) Change in capacitance due to displacement or pressure
(B) Change in resistance
(C) Magnetic induction
(D) Optical diffraction

12. MEMS pressure sensors are widely used in:
(A) Automotive and aerospace industries
(B) Audio amplifiers
(C) Power converters
(D) Optical fibers

13. In MEMS fabrication, bulk micromachining involves:
(A) Etching into the substrate material
(B) Building layers on top of a substrate
(C) Using magnetic fields to form structures
(D) Printing mechanical parts

14. Surface micromachining builds MEMS structures by:
(A) Depositing thin films layer by layer
(B) Cutting bulk material
(C) Welding micro-components
(D) Drilling holes

15. NEMS devices are advantageous due to:
(A) Extremely high sensitivity and speed
(B) Low temperature operation
(C) Large physical size
(D) Manual control

16. The primary material used in MEMS devices is:
(A) Silicon
(B) Copper
(C) Aluminum
(D) Iron

17. MEMS-based microphones convert:
(A) Acoustic pressure into electrical signals
(B) Light into voltage
(C) Current into heat
(D) Magnetic field into motion

18. MEMS accelerometers in smartphones are used for:
(A) Screen orientation detection
(B) Increasing signal strength
(C) Enhancing sound output
(D) Controlling brightness

19. A common actuation method used in MEMS devices is:
(A) Electrostatic actuation
(B) Hydraulic pressure
(C) Thermal conduction
(D) Optical stimulation

20. MEMS gyroscopes work on the principle of:
(A) Coriolis effect
(B) Seebeck effect
(C) Hall effect
(D) Photoelectric effect

21. The performance of MEMS sensors is significantly influenced by:
(A) Miniaturization and packaging
(B) Temperature only
(C) Magnetic field alone
(D) Weight of the device

22. NEMS-based sensors are often used for:
(A) Detecting biomolecules and gases at nanoscale
(B) High voltage switching
(C) Power transmission
(D) Heat dissipation

23. The main challenge in NEMS fabrication is:
(A) Maintaining structural stability at nanoscales
(B) Excessive weight
(C) Low sensitivity
(D) High mechanical rigidity

24. MEMS inertial sensors combine:
(A) Accelerometer and gyroscope
(B) Photodiode and magnetometer
(C) Thermistor and capacitor
(D) RTD and flow sensor

25. A MEMS resonator is used for:
(A) Frequency reference and filtering applications
(B) Power generation
(C) Temperature sensing
(D) Magnetic field measurement

26. The typical power consumption of MEMS sensors is:
(A) Very low
(B) Extremely high
(C) Moderate to high
(D) Negligible but unstable

27. MEMS technology is a key enabler for:
(A) Internet of Things (IoT) devices
(B) Large transformers
(C) Diesel engines
(D) Manual control systems

28. The integration of MEMS sensors with CMOS circuits allows:
(A) On-chip signal processing
(B) External control only
(C) Manual data reading
(D) Separate power supply

29. The Q-factor of a MEMS resonator represents:
(A) Energy loss and resonance sharpness
(B) Voltage gain
(C) Pressure difference
(D) Temperature coefficient

30. A key advantage of NEMS over MEMS is:
(A) Higher sensitivity and faster response time
(B) Larger structure
(C) Easier manual control
(D) Lower operational frequency