Deck 16: Applications of Electromagnetism

Question 1

In a ____ magnet, one pole of the magnet is formed on the core inside the coil, and the other pole is formed on the shell that surrounds the coil.

A)polarized
B)concentrated
C)lateral
D)lifting

Answer 1

D

Question 2

Mechanical vibration produces sound, and vibrations in the range from 20 to ____ vibrations per second can be heard by the human ear.

A)500
B)6,000
C)18,000
D)40,000

Answer 2

C

Question 3

One of the first applications of magnetic pull was lifting magnets, which are widely used for the transfer of scrap steel.

Answer 3

True

Question 4

Solenoids are electromagnetic coils that use a movable plunger to translate electrical energy into straight-line motion.

Question 5

For the better part of this century, millions of relays have been used as controls for very strong currents or high voltages, with a relatively small voltage or current source.

Question 6

Audio and video recorders alike operate on the principle of storing electronic signals by producing variations in the strength of a magnetic field and storing these signals by ____ the red oxide particles deposited along the length of the tape.

A)reducing
B)vibrating
C)magnetizing
D)collecting

Question 7

Some inventions of nearly 100 years ago, such as Joseph Henry's telegraph and Alexander Graham Bell's telephone, share no common elements with the most sophisticated electronic devices of modern times.

Question 8

The electric bell (or buzzer) demonstrates the principle of modifying a relay circuit to produce vibratory motion.

Question 9

Many electrical ____ instruments depend on the interaction of magnetic fields to move a tiny coil of wire, thereby causing a deflection of the meter movement.

A)deflecting
B)interacting
C)energy
D)measuring

Question 10

The picture on the ____ coating on the face of a TV picture tube is caused by an electron beam that sweeps the screen horizontally at 15,750 times per second and vertically at 60 times per second.

A)fluorescent
B)matte
C)shiny
D)clear

Question 11

This concept of relay ladder logic plays an important role in the solid-state devices known as programmable processors.

Question 12

A ____ can be described as a solenoid with switching contacts attached to a movable plunger.

A)coil
B)relay
C)hydraulic circuit
D)pneumatic circuit

Question 13

Relays have been used so extensively in industry that electrical blueprints are known as relay ladder diagrams or ____.

A)programmable controllers
B)negative grounds
C)relay ladder logic
D)modified blueprints

Question 14

One of the major applications of electrical energy is the production of ____ energy, such as with solenoids.

A)mechanical
B)potential
C)kinetic
D)chemical

Question 15

Early telephone receivers used a stationary coil consisting of many turns of ____ wrapped around the poles of a permanent horseshoe magnet.

A)fine wire
B)striated wire
C)twisted wire
D)thick wire

Question 16

Television picture tubes operate on the motor effect when they develop the picture on the screen.

Question 17

The term motor reaction is used to describe the phenomenon that a current-carrying wire within a magnetic field will move.

Question 18

The term motor effect only applies just to motors.

Question 19

The term generator ____ refers to the phenomenon that an electrical current can be generated simply by moving a wire through a magnetic field.

A)election
B)presentation
C)magnetism
D)action

Question 20

A relay is an electromagnetic switch, almost always with a single switching contact, that may open or close when the relay coil is energized.