Electric Motors 1

Devices consisting of a glass tube containing two small ferromagnetic (easily magnetized) metal reeds are called _____

• A) Magnetic reed switches

• B) Hall-Effect sensors

• C) Photoelectric sensors

• D) Capacitive sensors

The magnetic reed switch is a fast operating, single-pole, single-throw switch with a _____

• A) N.O contact

• B) N.C. contact

• C) Transistor output

• D) None of the above

_____ materials conduct magnetic lines of force very well

• A) Ferromagnetic

• B) Paramagnetic

• C) Diamagnetic

• D) All of the above

_____ materials, such as aluminum and platinum, conduct magnetic lines of force poorly

• A) Ferromagnetic

• B) Paramagnetic

• C) Diamagnetic

• D) A and B

The Hall-Effect sensor uses the principle of _____ to sense the presence of a magnetic object

• A) Inductive reactance

• B) Capacitive reactance

• C) Transduction

• D) Specular reflection

A Hall-Effect sensor that senses only _____ can help avoid false triggering of the sensor

• A) Metallic object

• B) Magnetic objects

• C) One magnetic polarity

• D) A and C above

If the Hall effect sensor's amplifier is _____, the output of the switch will rapidly change from one state to the other when a magnetic field is sensed by the device

• A) An NPN transistor

• B) A PNP transistor

• C) Analog

• D) Digital

The photoelectric sensor uses the principle of _____ to sense the presence of an object

• A) Photoreactance

• B) Phototransduction

• C) Photoconduction

• D) Photodiode

To keep a photoelectric sensor from being actuated by sunlight or regular lighting, sensors generally use _____ light

• A) Visible

• B) Ultraviolet

• C) X-ray

• D) Infrared

When light that strikes a highly polished target is reflected away at the same angle that it strikes the object's surface, it is called _____

• A) Retro

• B) Specular

• C) Diffuse

• D) Opposed sensing