Unit-II

What is the main principle of a motion sensor?

• To notice moving objects

• To detect sound waves

• To sense temperature changes

• To measure light intensity

Which type of motion sensor is commonly used in indoor alarms?

• Tomographic sensor

• Ultrasonic sensor

• Microwave sensor

• Passive Infrared (PIR) sensor

What is the main drawback of ultrasonic sensors?

• They are prone to false alarms

• They consume a lot of power

• They are expensive

• They are not sensitive enough

What is the primary application of potentiometers?

• Automated lighting control

• Energy conservation

• Control systems with feedback loop

• Home security systems

What is the main advantage of resolvers over other technologies?

• They are used in indoor alarms

• They are sensitive to temperature changes

• They are cheaper

• They offer reliability benefits

What is the purpose of an absolute optical encoder?

• To detect sound waves

• To measure light intensity

• To generate digital word identifying actual position of the shaft

• To sense temperature changes

What is the resolution of an absolute optical encoder with 4 concentric rings?

• 1 part in 8

• 1 part in 16

• 1 part in 4

• 1 part in 2

What does an incremental optical encoder consist of?

• Three coded discs and two photo-detect

• Two coded discs and two photo-detect

• One coded disc and two photo-detect

• Two coded discs and one photo-detect

What is the construction-wise characteristic of an incremental optical encoder?

• Simple and expensive

• Complex and accurate

• Simple, accurate, and expensive

• Simpler, less accurate, and less expensive

What is the main component of a magnetic encoder?

• All of the above

• Series of magnetic poles

• Rotating wheel or ring

• Sensing Circuit