Chpt 5 Part 1

Question 1

(T/F) The primary function of an X-ray system is to convert electric energy to nuclear energy

Answer 1

False
to electromagnetic energy

Question 2

Branch of physics that deals with stationary electrical charges

Answer 2

electrostatics

Question 3

What will give an object an electrical charge?

Answer 3

A differing number of electrons and protons

Question 4

What is caused by the movement of negative electric charges

Answer 4

electrification

Question 5

3 Methods that cause electrification

Answer 5

friction - removal of electrons from one object by rubbing it w/ a different object
contact - a charged object touches an uncharged object and the second object acquires the same charge
induction - strong object will influence a weak object

Question 6

Friction is most likely to happen in hot and humid conditions

Answer 6

False
cold and low humidity

Question 7

A negatively charged object will give electrons to what object

Answer 7

neutral object

Question 8

Electrostatics Law (4) that describes how electric charges interact with each other

Answer 8

• repulsion/attraction
• Coulomb’s law (ISL)
• Distribution
• Concentration

Question 9

Coulomb’s law measures what?

Answer 9

the magnitude of the electrostatic force

Question 10

Electrical charges reside on the _____ surface of conductors and are equally distributed throughout ____?

Answer 10

external
non-conductors

Question 11

(T/F) Electric charge of a conductor has its greatest concentration along the sharpest curvature of its surface

Answer 11

True

Question 12

Only what charges move along a conductor?

Answer 12

negative

Question 13

What is a substance in which the electrons will flow easily?

Answer 13

conductor

Question 14

The study of electric charges in motion

Answer 14

electrodynamics

Question 15

(T/F) Electric current always flows in the same direction as the electron flow

Answer 15

False
opposite direction

Question 16

The ability of a material to allow the free flow of electrons

Answer 16

conductivity

Question 17

What is a material that does not allow electron flow?

Answer 17

Insulator

Question 18

Material that allows it to be either a conductor or insulator

Answer 18

semi-conductor

Question 19

Has no resistance to the flow of electrons

Answer 19

superconductor

Question 20

Examples of a superconductor

Answer 20

ceramics, titanium, niobium

Question 21

When resistance is _____ and the _____ is a closed path an electric circuit is created

Answer 21

controlled
conductor

Question 22

Current is measured in?

Answer 22

Amperes

Question 23

3 conditions that allow current to flow

Answer 23

• vacuum (x-ray tube)
• gas (fluorescent light)
• metallic conductor (copper wire)

Question 24

inhibits the flow of electrons

Answer 24

resistor

Question 25

provides electric potential

Answer 25

battery / generator

Question 26

momentarily stores electric charge

Answer 26

capacitor

Question 27

measure electric current

Answer 27

ammeter

Question 28

measures electric potential

Answer 28

voltmeter

Question 29

turns the circuit on or off

Answer 29

switch

Question 30

increases or decreases voltage by a fixed amount

Answer 30

transformer

Question 31

a variable resistor

Answer 31

rheostat

Question 32

allows electrons to flow only in one direction

Answer 32

diode

Question 33

3 factors that characterize a simple circuit

Answer 33

potential difference current resistance

Question 34

difference in electrical potential energy between 2 points in a circuit

Answer 34

potential difference

Question 35

what gives the electrons the pull to move through the conductor

Answer 35

potential difference

Question 36

potential difference is measured in?

Answer 36

volts

Question 37

the amount of electrical charges per second

Answer 37

current (amperes)

Question 38

anything that opposes or hinders the flow of electrical current

Answer 38

resistance (ohm)

Question 39

Inherent resistance is dependent on 4 things

Answer 39

type of conducting material length of wire diameter temperature

Question 40

Ohm's Law

Answer 40

voltage across the total circuit is equal to the current multiplied by the resistance

Question 41

Series vs Parallel circuits

Answer 41

series - all elements are connected in a line parallel - connected at ends