Title: Sensors and Interfacing
Course: Intro to Control Devices (IC 108-IC 108) > Section: Assessments

Q: ______________ is a measure of the amount of light energy that falls on the receiver beyond the minimum amount of light required to operate the sensor amplifier.
- Sensitivity
- Excess gain
- Field of view
A: Sensitivity

Q: A __________ inductive sensor has the longer sensing range.
- non-shielded
- shielded
A: non-shielded

Q: A linear inductive proximity detector uses a Schmitt trigger in its internal circuitry.
- True
- False
A: False

Q: A proximity detector with a 2-inch diameter has a sensing distance that is twice as far as a one-inch sensor.
- True
- False
A: True

Q: An inductive proximity detector senses ___________.
- metallic materials
- nonmetallic materials
- both a and b
A: metallic materials

Q: Current flows in a light detection device when ____________ collide with its PN junction.
- electrons
- protons
- holes
- photons
A: electrons

Q: Excluding the white wire, all connections of a four-wire sinking sensor are identical to a three-wire sensor.
- True
- False
A: True

Q: Hall-effect sensors are capable of switching at higher frequencies than inductive proximity detectors.
- True
- False
A: True

Q: Hall-effect sensors are capable of producing ___________.
- linear output signal that is proportional to the distance of the object to the sensor
- an on or off output signal, depending on the distance the object is placed from the sensor
- a or b, but not both in the same housing
A: linear output signal that is proportional to the distance of the object to the sensor

Q: If a film or oil or dirt forms on the head of a sensor, it will not affect the operation of the inductive type, but it may affect the capacitive type.
- True
- False
A: True

Q: If only 25 percent of the light produced by an emitter is received by the detector due to unclear air, an excess gain of __________ is required to overcome the loss of light.
- 1x
- 2x
- 4x
- 8x
A: 1x

Q: If the voltage at the output lead of a three-wire sensor decreases when the sensor is activated, it is a _____________ device.
- sourcing
- sinking
A: sourcing

Q: Infrared is a ________________ light to the human eye.
- visible
- invisible
A: visible

Q: The advantage of a phototransistor over a photodiode detector is that ____________.
- it operates at higher frequencies
- it has greater light sensitivity
- it is linear
- it has small temperature coefficients
A: it operates at higher frequencies

Q: The color mark sensing method ______________.
- can detect two colors on the same surface
- can detect two colors from separate objects
- both a and b
A: can detect two colors on the same surface

Q: The disadvantage of a two-wire sensor is that current flows through it when it is de-activated.
- True
- False
A: True

Q: The inductive proximity detector senses only a metal target and the capacitor proximity senses only a nonmetallic target.
- True
- False
A: False

Q: The recommended space between the target and sensor head of an inductive proximity sensor is half the nominal sensing distance.
- True
- False
A: True

Q: The retroreflective method of light detection uses the _______________ mode to detect an object.
- light-to-dark
- dark-to-light
A: light-to-dark

Q: The term load refers to the ____________.
- equipment to which the sensor output is applied
- sensor in reference to the equipment to which it provides its signal
A: equipment to which the sensor output is applied

Q: What determines the color difference in light?
- amplitude
- power
- frequency
A: amplitude

Q: When light strikes a photoresistor, its resistance is ____________.
- low
- high
A: low

Q: Which condition causes the output voltage of a Hall-effect device to be produced?
- detecting the target
- not detecting a target
A: detecting the target

Q: Which of the following functions are performed by limit switches?
- detecting the position of an object
- detecting the size of an object
- counting parts
- preventing movement of an object outside a safe zone
A: detecting the position of an object

Q: Which of the following materials can be detected by a capacitive proximity detector?
- liquids
- nonmetallic solids
- powders
- granular materials
A: liquids