Generators and Motors

Question 1

another name for a generator is a

Answer 1

dynamo

Question 2

what converts mechanical energy to electrical energy

Answer 2

a generator or dynamo

Question 3

what converts electrical energy to mechanical energy

Answer 3

a motor

Question 4

components of a generator

Answer 4

powerful electromagnet and an armature

Question 5

coil of wire mechanically rotated through a magnetic field

Answer 5

armature

Question 6

what turns an armature

Answer 6

mechanical energy

Question 7

a simple generator is made up of

Answer 7

a single loop armature rotating between the poles of a magnet

Question 8

what is the armature connected to in a simple generator AC?

Answer 8

slip rings

Question 9

what are the rings connected to in a simple generator

Answer 9

an external circuit of resistance

Question 10

purpose of carbon brushes in simple generator

Answer 10

carbon brushes rest firmly against the rings, current produced is “brushed off” when the armature rotates

Question 11

what is the armature connected to in a simple generator DC?

Answer 11

commutator ring

Question 12

In a simple AC generator, as an armature moves 360 degrees through a magnetic field, what is produced?

Answer 12

an EMF is produces in a direction opposite to the movement of the armature

Question 13

In a simple AC generator, as the armature moves to 90 degrees, the EMF ____

Answer 13

increases

Question 14

when is EMF at its peak in a simple AC generator?

Answer 14

at 90 degrees to the flux lines

Question 15

when is EMF at its negative peak in a simple AC generator?

Answer 15

at 90 degrees in the opposite direction from origin

Question 16

how many cycles per second are produced in the US?

Answer 16

60 cycles per second

Question 17

60 complete rotations of an armature in 1 second is how many cycles and how many alterations in direction?

Answer 17

60 cycles and 120 alterations in direction

Question 18

total AC resistance is known as

Answer 18

impedance

Question 19

impedance or (Z) =

Answer 19

electrical resistance + inductance reactance + capacitance reactance

Question 20

AC Ohm’s law formula

Answer 20

V = I x Z (Z = ER + IR + CR)

Question 21

inductance reactance

Answer 21

bucking of current as a result of the changing direction of the EMF

Question 22

capacitance reactance

Answer 22

the hindrance of current due to the capacity overload of a capacitor (capacitance)

Question 23

Electrical resistance (resistivity)

Answer 23

material coefficient / length / area

Question 24

what replaces the slip ring in a DC generator?

Answer 24

commutator ring

Question 25

how does armature move in a DC generator

Answer 25

rotates 180 degrees and then back

Question 26

DC generator creates what kind of current

Answer 26

pulsating direct current

Question 27

what type of current comes through the wall?

Answer 27

AC or alternating current

Question 28

what type of current is used in the production of x-rays?

Answer 28

DC or direct current

Question 29

advantages of alternating current

Answer 29

AC is needed to operate transformers, less power loss than DC, can transmit lower amperage, higher voltage than DC

Question 30

what do electric motors convert

Answer 30

electrical to mechanical energy

Question 31

define motor principle

Answer 31

whenever a conductor carrying current is placed in a magnetic field, there is a force or side thrust produced on the conductor

Question 32

what must an electric motor have

Answer 32

conductor carrying current and a magnetic field

Question 33

which motors are synchronous

Answer 33

AC motors, Armature rotates at the same RPM as the generator

Question 34

what rule is used for the motor effect?

Answer 34

right hand rule

Question 35

thumb purpose in right hand rule

Answer 35

direction of the conductor

Question 36

index finger purpose in right hand rule

Answer 36

direction of the magnetic field

Question 37

middle finger purpose in right hand rule

Answer 37

direction of the current produced in the conductor