Physics Unit 5 and 6 Review

Question 1

Motor

Answer 1

Turns electrical energy into mechanical

Question 2

Generator

Answer 2

Turns mechanical energy into electrical

Question 3

Step up Transformer

Answer 3

Increases voltage, decreases current

Question 4

Step down transformer

Answer 4

Decreases voltage, increases current

Question 5

Purpose of transformer

Answer 5

select applied KV

Question 6

Four types of transformers and define

Answer 6

Open core-iron cores inserted in coils
Air core-2 coils side by side
Shell-Cinderblock looking iron core and prism/second wrapped around center post of coil
Closed- one continuous loop of core with windings wrapped

Question 7

What transformer is least efficient

Answer 7

Air

Question 8

What transformer is most efficient

Answer 8

Shell

Question 9

Difference between air core and open core

Answer 9

Air core has no core and open core has ferromagnetic core

Question 10

What are transformers wrapped with to help improve efficiency

Answer 10

laminated silicon steel to hold in power

Question 11

3 ways to lose power in transformers

Answer 11

Copper-resistance in conductor itself because of diameter and length
Hysteresis: AC fluctuations and realignment of magnetic domain
Eddy: current swirling in the core

Question 12

Transformers work on what principle

Answer 12

Mutual induction

Question 13

What current works best with transformers

Answer 13

AC

Question 14

Transfomer Law

Answer 14

Vp/Vs=Np/Ns

Question 15

Purpose of Autotransfomers

Answer 15

select the KV

Question 16

Autotransfomers work on the principle of

Answer 16

Self induction

Question 17

How do you determine the amount of voltage per tapped turn

Answer 17

dividing total amount of voltage going into by the total turns

Question 18

auto transformers are also called

Answer 18

Variable ratio transformers

Question 19

3 phase 6 pulse formula

Answer 19

MAsxKVx1.35

Question 20

3 phase 12 pulse formula

Answer 20

MAsxKVx1.41

Question 21

What turns the rotor in an induction motor

Answer 21

rotating magnetic field

Question 22

Where do you find an induction motor in Xray equipment

Answer 22

target/xray tube

Question 23

What types of devices are syncronous motors found in

Answer 23

Clocks and timers

Question 24

What accelerates the electrons from the cathode to the anode

Answer 24

KVP or applied voltage

Question 25

The focusing cup can be made of what 2 metals

Answer 25

nickel

molybdenum

Question 26

Regular speed motor vs high speed

Answer 26

3600 to 10000-12000 RPMS

Question 27

Why are tungsten and thorium used as filament materials

Answer 27

high heat capacity, high atomic number, for longer ife

Question 28

What temp does thermoinic emission occur

Answer 28

2200°c

Question 29

Anode Heel Effect

Answer 29

absorbs reduction on intensity because the anode absorbs some of the beam

Question 30

Dual focus tubes

Answer 30

SFS/LFS detail

2 focal spot sizes in a tube

Question 31

Line focus principle

Answer 31

as long as the target angle is less than 45° the effective focal spot it was always be smaller than AFS

Question 32

What eventually causes the demise of xtray tubes

Answer 32

Fillament breaking-heat in general

Question 33

What are rotor bearings made out of that keeps them spinning smoothly

Answer 33

Metallic barium or silver

Question 34

Why is the tube immersed in oil

Answer 34

prevents shock and electrical insulation

Question 35

3 transformer types

Answer 35

auto
high tension
fillament