# 250+ TOP MCQs on Transducers – Characteristic Parameters and Answers

Mechatronics Questions and Answers for Freshers on “Transducers – Characteristic Parameters”.

1. What is the nature of resistance to light intensity graph of an LDR (Light dependent resistor)?
a) Increasing
b) Decreasing
c) Parabolic
d) Constant
Clarification: The resistance to light intensity graph of an LDR (Light dependent resistor) has a decreasing nature. As the intensity of the light falling on the LDR (Light dependent resistor) increases, the value of its resistance decreases.

2. What is the absolute error of an observation taken by an ultrasonic sensor which predicts the distance of an object to be 5.1 cm but the actual value is 5 cm?
a) 1.02
b) 0.1
c) 0.01
d) 1
Clarification:Given: Actual Value=5cm
Measured Value=5.1cm
Absolute error=Measured Value-Actual Value
Absolute error=5.1cm-5cm=>0.1cm

3. What is the relative error of an observation taken by an ultrasonic sensor which predicts the distance of an object to be 3.1 cm but the actual value is 3 cm?
a) 1.03
b) 0.1
c) 0.033
d) 1
Clarification: Given: Actual Value=3cm
Measured Value=3.1cm
Absolute error=Measured Value-Actual Value
Absolute error=3.1cm-3cm => 0.1cm
Relative error=Absolute error/Actual value
Relative error=0.1/3=>0.033

4. What is the sensitivity of a sensor if the difference between two alternative output observations is 0.6 and difference between two alternative input observations is 0.2?
a) 3
b) 0.6
c) 0.2
d) 2
Clarification: Given: Change in output=0.6
Change in input=0.2
Sensitivity=Change in output/Change in input
Sensitivity=0.6/0.2=>3

5. What is the nature of resistance to light intensity graph of aB57211P0100M301 thyristor?
a) Increasing
b) Decreasing
c) Parabolic
d) Constant
Clarification: The resistance to temperature graph of a B57211P0100M301 thermistor has a decreasing nature. When the temperature of the B57211P0100M301 increases, then the value of its resistance decreases. And vice versa happens when temperature decreases.

6. The intensity of light is inversely proportional to the resistance of a photo resistor.
a) True
b) False
Clarification: The intensity of light is inversely proportional to the resistance of a photo resistor. When the intensity of light falling on the photo resistor increases its resistance decreases. The resistance to light intensity graph of a photo resistor has a decreasing nature.

7. Transformer is a type of transducer.
a) True
b) False
Clarification: Transformer is not a type of transducer. Transducers are devices that can convert one form of energy to some different form, whereas a transformer steps up or steps down voltage or current. It does not changes the form of energy

8. The resistance of a thermistor is directly proportional to its temperature.
a) True
b) False
Clarification: The resistance of a thermistor is inversely proportional to its temperature. When the temperature of the thermistor increases, then the value of its resistance decreases. And vice versa happens when temperature decreases.

9. What is the sensitivity of a sensor if the difference between two alternative output observations is 0.4 and difference between two alternative input observations is 0.2?
a) 0.4
b) 0.6
c) 0.2
d) 2
Clarification: Given: Change in output=0.4
Change in input=0.2
Sensitivity=Change in output/Change in input
Sensitivity=0.4/0.2=>2

10. What is the relative error of an observation taken by an infrared sensor which predicts the distance of an object to be 4cm but the actual value is 3.8cm?
a) 1.03
b) 0.0526
c) 0.033
d) 1
Clarification: Given: Actual Value=3.8cm
Measured Value=4cm
Absolute error=Measured Value-Actual Value
Absolute error=4cm-3.8cm=>0.2cm
Relative error=Absolute error/Actual value
Relative error=0.2/3.8cm=>0.0526

11. All sensors are transducers.
a) True
b) False
Clarification: All sensors are transducers. Transducers are devices that can convert one form of energy to some different form; when a sensor senses an object it converts it into machine readable electrical signals therefore it’s a transducer. But all transducers are not sensors.

12. What is the nature of resistance to temperature graph of a thermistor?
a) Increasing
b) Decreasing
c) Increases and then decreases
d) Constant
Clarification: The resistance to temperature graph of a thermistor has a decreasing nature. When the temperature of the Thermistor increases, then the value of its resistance decreases. And vice versa happens when temperature decreases.

13. What is the relative error of an observation taken by an ultrasonic sensor which predicts the distance of an object to be 2.3 cm but the actual value is 2.1cm?
a) 1.03
b) 0.2
c) 0.0869
d) 1
Clarification: Given: Actual Value=2.3cm
Measured Value=2.1cm
Absolute error=Measured Value-Actual Value
Absolute error=2.3cm-2.1cm=>0.2cm
Relative error=Absolute error/Actual value
Relative error=0.2/2.3=>0.0869

14. What is the absolute error of an observation taken by an Infrared sensor which predicts the distance of an object to be 3.2 cm but the actual value is 2.9cm?
a) 1.1
b) 0.3
c) 0.03
d) 1
Clarification: Given: Actual Value=2.9 cm
Measured Value=3.2cm
Absolute error=Measured Value-Actual Value
Absolute error=3.2cm-2.9cm=>0.3cm

15. What is the nature of resistance to light intensity graph of a Photo resistor?
a) Increasing
b) Decreasing
c) Parabolic
d) Constant