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Mechatronics Assessment Questions and Answers on “Displacement Sensors”.
1. An Eddy current type displacement sensor can detect which types of objects?
a) Wooden Objects
b) Metal Objects
c) Plastic Objects
d) Bricks
Answer: b
Clarification: Eddy current type displacement sensor can detect metal objects because it uses high frequency magnetic field for the detection of objects. When this metallic object come in the range of magnetic field, due to the electromagnetic induction, eddy current starts to flow through the object in vertical direction which causes a change in the impedance of the sensor. This change in impedance is used to measure the distance.
2. Which displacement sensor has the slowest response time among Optical type, Eddy current type, Ultrasonic type and Laser focus type?
a) Optical Type
b) Eddy Current Type
c) Ultrasonic Type
d) Laser Focus Type
Answer: c
Clarification: Ultrasonic type displacement sensor has the slowest response time among all the above mentioned type sensors. It’s so because it uses ultrasonic sound waves for the measurement while Optical and Laser type uses light for the measurement which is much faster than the ultrasonic waves. Eddy current type sensors uses high frequency magnetic field which is also faster than the ultrasonic waves.
3. Which displacement sensor has the lowest accuracy to measure displacement among Optical type, Eddy current type, Ultrasonic type, Laser focus type?
a) Optical Type
b) Eddy Current Type
c) Ultrasonic Type
d) Laser Focus Type
Answer: c
Clarification: Ultrasonic type displacement sensor has the lowest accuracy to measure displacement among all the above mentioned type sensors. It’s so because it uses ultrasonic sound waves for the measurement while Optical and Laser type uses light for the measurement which is much faster than the ultrasonic waves and also has quick response time. Eddy current type sensors uses high frequency magnetic field which too has a greater response time compared the ultrasonic type which make it more accurate in measuring distances.
4. What is the International System of length used to measure displacement?
a) Metre
b) Kilo Meter
c) Centimetre
d) Yards
Answer: a
Clarification: The international system of length, also known as the SI unit of length is metres. In MKS system the standard unit of measuring length is metre, mass in kilogram and time in seconds. This MKS unit is mostly used in engineering field, but for basic physics field the most common system is the CGS system where the unit of measurement of length is in centimetres, mass in grams and time in seconds.
5. Displacement sensors can also be used to measure an object’s thickness, height and width.
a) True
b) False
Answer: a
Clarification: In addition to measure the relative displacement of an object, these sensors can also be used to measure the dimensions of an object. This measurement can be done either by non-contact methods by using light, sound waves or through making an actual contact with this object.
6. Interferometer can be used for accurate measurement of distance.
a) True
b) False
Answer: a
Clarification: Interferometer can be used for accurate measurement of distance. It can measure small things with incredibly high accuracy by comparing light or radio beams. It uses the wave pattern interfaces to measure the distance by comparing reflected or refracted waves coming from objects.
7. ECS in context to displacement measurement stands for ____
a) Electronic Chirp Scaling
b) Extended Chirp Scaling
c) Electronic Chip Scaling
d) Extended Chip Scaling
Answer: b
Clarification: ECS in context to displacement measurement stands for Extended chirp scaling. It’s a commonly used algorithm used for SAR (Synthetic Aperture Radar) imaging.
8. Bently nevada 3300 xl 5/8mm in an example of which type of sensor?
a) Infrared Sensor
b) Proximitor Sensor
c) Ultrasonic Sensor
d) Temperature Sensor
Answer: b
Clarification: Bently nevada 3300 xl 5/8mm in an example of proximitor sensor. This sensor is mostly used in industrial sector, it measures the very small movements due to vibrations caused by the big machinaries. It helps the employee to monitor and control the vibrations in machines.
9. Potentiometer as a displacement sensor works on the principle of ________
a) Mutual Inductance
b) Self Inductance
c) Variable Resistance Transduction
d) Hall Effect
Answer: c
Clarification: Potentiometer as a displacement sensor works on the principle of Variable resistance transduction. They are linear or rotary potentiometers which converts this rotation in potential difference and this potential difference is used for calculating the displacement.
10. In capacitive sensors the displacement is measured with respect to change in which internal factor of the sensor?
a) Capacitance
b) Resistance
c) Inductance
d) Effervescence
Answer: a
Clarification: In capacitive sensors the displacement is measured with respect to change in capacitance of the sensor. The displacement changes the area of overlap of the charged plates also it moves the dielectric between the plates which results in change of the dielectric constant and hence both the factors lead in the overall change of the capacitance.
Mechatronics Assessment Questions,