Sensors and transducers MCQs December 24, 2025November 20, 2024 by u930973931_answers 20 min Score: 0 Attempted: 0/20 Subscribe 1. . What is the primary function of a sensor? (A) To convert one form of energy to another (B) To store electrical energy (C) To detect physical or chemical changes in the environment and convert them to electrical signals (D) To process data and provide output 2. . A transducer is defined as a device that: (A) Converts electrical energy into mechanical energy (B) Converts one form of energy into another (C) Processes and amplifies electrical signals (D) Stores energy for future use 3. . Which of the following is a key characteristic of a sensor? (A) It can only measure temperature (B) It is an active component (C) It converts physical parameters into an electrical signal (D) It requires no external power 4. . Which of the following sensors is used to measure temperature? (A) Accelerometer (B) Thermocouple (C) Pressure sensor (D) Ultrasonic sensor 5. . A pressure sensor typically measures: (A) Temperature (B) Force per unit area (C) Light intensity (D) Sound waves 6. . Which of the following sensors is used to detect the presence of an object? (A) Proximity sensor (B) Thermistor (C) Photodiode (D) Strain gauge 7. . A thermocouple works on the principle of: (A) Piezoelectric effect (B) Photovoltaic effect (C) Seebeck effect (D) Magnetoresistive effect 8. . A strain gauge works by: (A) Measuring the change in resistance due to deformation (B) Detecting light intensity (C) Measuring temperature changes (D) Converting sound waves into electrical signals 9. . Which of the following principles is used by capacitive sensors to measure displacement? (A) Change in capacitance (B) Change in resistance (C) Change in voltage (D) Change in light intensity 10. . Which of the following is an application of a humidity sensor? (A) Detecting the presence of gases in the air (B) Measuring air moisture levels in weather stations (C) Measuring temperature variations in circuits (D) Measuring the intensity of light 11. . What type of sensor would be used to measure the speed of a rotating object? (A) Gyroscope (B) Tachometer (C) Photodetector (D) Accelerometer 12. . Which of the following sensors is commonly used in a heart rate monitor? (A) Thermocouple (B) Photoplethysmographic sensor (C) Pressure sensor (D) Gas sensor 13. . An example of a passive transducer is: (A) Thermocouple (B) Piezoelectric sensor (C) Strain gauge (D) Light-emitting diode (LED) 14. . Which of the following is an example of an active transducer? (A) Thermistor (B) Strain gauge (C) Photovoltaic cell (D) Piezoelectric crystal 15. . What is the main difference between an active and a passive transducer? (A) Active transducers require an external power supply, while passive transducers do not (B) Active transducers can amplify signals, while passive transducers cannot (C) Passive transducers can generate energy, while active ones cannot (D) Active transducers are used for mechanical measurements, while passive ones are used for electrical measurements 16. . The sensitivity of a sensor refers to: (A) The minimum detectable signal (B) The ratio of output signal to the input signal (C) The accuracy of the sensor (D) The speed of the sensor’s response 17. . What does the resolution of a sensor refer to? (A) The sensor’s ability to detect very small changes in the measured quantity (B) The speed at which the sensor provides data (C) The maximum value a sensor can measure (D) The power consumption of the sensor 18. . What is the purpose of calibration in sensors? (A) To reduce the sensor’s size (B) To correct the sensor’s output based on known standards or references (C) To increase the sensor’s sensitivity (D) To improve the sensor’s power consumption 19. . Which of the following is commonly used to convert the analog output of a sensor to a digital signal? (A) Analog-to-Digital Converter (ADC) (B) Digital-to-Analog Converter (DAC) (C) Operational Amplifier (D) Voltage regulator 20. . What is signal conditioning in the context of sensor applications? (A) Converting the output of a sensor into a usable form (B) Modulating the sensor’s signal for better transmission (C) Filtering out noise from the sensor’s output (D) All of the above