Module 1

Question 1

Are widely used for the
purpose of converting energy
from one form to another.

Answer 1

Rotating Electrical Machines

Question 2

Takes place between well known Pairs of FORMS OF ENERGY

Answer 2

Energy Conversion Process

Question 3

7 Types of Energy

Answer 3

Mechanical, Electrical, Sound, Chemical, Light, Heat, Nuclear

Question 4

This law states that energy can neither be created nor destroyed. It can only be transformed from one form to another.

Answer 4

First Law of Thermodynamics: “Law of Conservation of Energy”

Question 5

When energy is transformed from one form to another, some of the input energy is turned into a highly disordered form of energy, like heat,
which resulted to energy loss.

Answer 5

Second Law of Thermodynamics: “Law of Increased Entropy”

Question 6

A device, having a unique purpose, that augments or replaces human or animal effort for the
accomplishment of physical tasks.

Answer 6

Machine

Question 7

Is a rotary electro-mechanical energy conversion device that converts mechanical energy to
direct current (DC) electrical energy or DC electrical energy to mechanical energy.

Answer 7

DC Machine

Question 8

Conversion of Energy in Electrical Generator

Answer 8

Mechanical Energy to Electrical Energy

Question 9

Conversion of Energy in Electrical Motor

Answer 9

Electrical Energy to Mechanical Energy

Question 10

A machine generates electrical energy for use in
an external circuit.

Answer 10

Electric Generator

Question 11

A mechanical machine that drives (rotates) the electrical generator

Answer 11

Prime mover

Question 12

an initial source of motive power (rotation) designed to receive and modify force and motion as supplied by some natural or chemical source and apply them to drive a machinery.

Answer 12

Prime Mover

Question 13

A machinery that produces
rotational mechanical energy
to drive external physical loads.

Answer 13

Electrical Motor

Question 14

“Whenever a conductor is placed in a varying magnetic
field, an electromotive force is induced.”

Answer 14

Faraday’s Fist Law of Electromagnetic Induction

Question 15

the stationary part of the DC generator

Answer 15

Stator

Question 16

The moving/rotating part of the DC generator

Answer 16

Rotor

Question 17

– magnets or electromagnets that creates magnetic lines of force to
be cut by the armature conductors.
– always work in pairs

Answer 17

Poles

Question 18

– houses the entire machine
– where the magnets/poles are mounted.

Answer 18

Yoke

Question 19

– holds the poles together and spread the flux evenly.

Answer 19

Pole Shoe

Question 20

Parts of a DC Generator that are under the Stator

Answer 20

Yoke, Pole Shoe, Pole

Question 21

– a laminated steel core that holds and contains the current carrying
conductors (windings) on its conductor slots.
– also called as the armature core

Answer 21

Core

Question 22

– copper conductors that are wounded around the core that cuts
the magnetic lines of force.
– also called as the armature conductors

Answer 22

Windings

Question 23

– coupled/connected to the prime mover that rotates the core.

Answer 23

Shaft

Question 24

Parts of a DC Generator that are under the Rotor

Answer 24

Core, Windings, Shaft

Question 25

termination point of the armature windings and periodically reverses the direction of the current flow to an external circuit.

Answer 25

Commutator

Question 26

makes the current change direction every half-rotation.

Answer 26

Split Rings

Question 27

merely maintains a connection between the moving rotor and the stationary stator. No commutation process occurring.

Answer 27

Slip Ring

Question 28

harvest the current from the rotating commutator. It always work in pairs.

Answer 28

Carbon Brushes

Question 29

“The magnitude of the generated voltage is directly proportional to the rate at which a conductor cuts magnetic lines of force.”

Answer 29

Second Law of Electromagnetic Induction

Question 30

measuring device that measures magnetic flux, ∅ of a magnet system or a single magnet

Answer 30

Flux Meter

Question 31

An individual piece of wire placed in the slots of the DC machine.

Answer 31

Conductor

Question 32

Formed by looping wires or conductors around the armature.

Answer 32

Turn

Question 33

Made when one or more turns of wire (single-turn coil or multi-turn coil) are placed in an almost similar magnetic position inside the DC machine.

Answer 33

Coil

Question 34

A part of the coil in each conductor slot.

Answer 34

Coil Side

Question 35

A type if winding that Forms a loop as it expands around the armature core.

Answer 35

Lap Winding

Question 36

A type if winding that Forms a wave as it expands around the armature core.

Answer 36

Wave winding

Question 37

Combination of lap and wave coil windings.

Answer 37

Frog-leg winding

Question 38

➢ In this winding, the coil ends of each armature coil (start and end) is connected to adjacent commutator segments. ➢ The finishing end of one coil is situated under the same pair of poles of the starting end of the next coil. ➢ The number parallel paths and brushes is equal to the number of poles. ➢ This type of winding is used for high- current and low-voltage rating generators.

Answer 38

Lap Winding

Question 39

➢ In this winding, the coil ends of each armature coil (start and end) is separated by the distance between two pairs of poles. ➢ The finishing end of the one coil is connected to the starting end of the next armature coil situated under different pairs of poles. ➢ The number parallel paths and brushes is always 2. ➢ This type of winding is used for low- current and high-voltage rating generators.

Answer 39

Wave winding