Electricity

Question 1

in electricity, current is

Answer 1

the movement of electrons

Question 2

electric current

Answer 2

how much charge (how many electrons) pass a certain point in a circuit per unit time

Question 3

each electron has a charge of

Answer 3

1.60217733 x10^-19 coulombs

Question 4

a coulomb

Answer 4

unit of measure of electric charge

Question 5

6.24 x10^18 electrons carry charge of

Answer 5

1 coulomb

Question 6

movement of 1 coulomb of charge in 1 second is

Answer 6

1 ampere (amp)

Question 7

1 amp of current =

Answer 7

1 coulomb/sec

Question 8

the flow of electrons (electric current) is inversely proportional to

Answer 8

resistance

Question 9

electromotive force

Answer 9

potential difference of electric charges from one area to the next

(pushes the electrons through the resistance)

Question 10

the greater the potential difference

Answer 10

the greater the push of electrons through a resistance and the greater the flow of electrons

Question 11

potential difference is directly proportional to

Answer 11

the flow of electrons (electric current)

Question 12

equation for the relation of flow of electrons, potential difference, and resistance

Answer 12

I = V/R
I = current, V = voltage, R = resistance

Question 13

the potential difference is measured in

Answer 13

Volts

Question 14

current is quantity of electrons measured in

Answer 14

amperes (amps)

Question 15

resistance is measured in

Answer 15

Ohms

Question 16

current can only flow if it gets

Answer 16

pushed

Question 17

2 forms of electrical current flow thru a conductor

Answer 17

alternating current (Volts-AC)
direct current (Volts-DC)

Question 18

Impedance

Answer 18

Z

consist of resistance plus other factors that effect electron flow

Question 19

examples of EMF

Answer 19

static electricity, lightening

Question 20

the product of voltage and current

Answer 20

watt (unit of power)

Question 21

amount of electrical work done measured in

Answer 21

watt-sec which = joules

Question 22

energy produced by defibrillator is measured in

Answer 22

watt-sec

Question 23

energy consumption in a home is measured in

Answer 23

kilowatt-hours

Question 24

a closed loop must have

Answer 24

completed circuit with driving pressure (V), to force a current (I), to flow thru a resistance (R)

Question 25

conductor

Answer 25

any substance that permits a flow of electrons (loosely attached and easily lost electrons)

Question 26

current flow follows a gradient from

Answer 26

high voltage to low voltage | seeks path of least resistance

Question 27

nonconductors or insulators

Answer 27

have tightly bound electrons which do not permit electron flow (glass, rubber, plastic, dry wood, pure water)

Question 28

in direct current the electron flow is

Answer 28

always in the same direction

Question 29

in alternating current the electron flow

Answer 29

reverses direction at regular intervals, measured in Hz (cycles per second)

Question 30

when dealing with AC circuits the flow of current is opposed by

Answer 30

impedance

Question 31

inductance generates

Answer 31

an electromagnetic field which creates increased resistance

Question 32

capacitance generates

Answer 32

capacitance current in electrical circuit that creates a decrease resistance in the circuit

Question 33

capacitance is

Answer 33

a measure of substance's ability to store a charge

Question 34

in DC circuit the capacitor plates are

Answer 34

charged by a voltage source and the flow of current is momentary

Question 35

in AC circuit the capacitor plates

Answer 35

permits current of flow even when the circuit is not completed by a resistance

Question 36

stray capacitance

Answer 36

power cord, consists of 2 insulated wires next to each other will generate capacitance just being plugged in

Question 37

as frequency increases

Answer 37

impedance to electron flow will decrease

Question 38

electrosurgical units use

Answer 38

high frequency currents so they have low impedance

Question 39

a basic capacitor consists of

Answer 39

2 parallel conducting plates separated by an insulating layer (dielectric)

Question 40

a capacitor is an electrical device used for

Answer 40

storing electric charge

Question 41

what makes substances like iron, cobalt, and nickel magnetic

Answer 41

most of the electrons spin in the same direction

Question 42

when electricity runs through a coil of wire

Answer 42

it produces a magnetic field

Question 43

in an AC circuit, inductance can

Answer 43

electromagnetically generate an opposing electromotive force in a nearby wire

Question 44

bending a wire into a coil

Answer 44

amplifies the magnetic field

Question 45

the hot conductor

Answer 45

carries the current thru the impedance

Question 46

the neutral conductor

Answer 46

returns the current to the source

Question 47

the amount of current flowing thru the conductors depends on

Answer 47

the amount of impedance

Question 48

high impedance

Answer 48

low current flow

Question 49

low impedance

Answer 49

high current flow

Question 50

a short circuit or fault is

Answer 50

a condition in which there is zero impedance with a high current flow

Question 51

electric shock can occur

Answer 51

by contacting AC or DC current

Question 52

electrical shock occurs when

Answer 52

a person becomes part of or completes an electric circuit

Question 53

for a shock to occur

Answer 53

must contact the electric circuit at 2 points and a voltage source causing current to flow

Question 54

in the OR there are 2 categories of electric shock

Answer 54

macroshock - large amount >1mA | microshock - small amount <1mA

Question 55

a PA catheter with conducting fluid can

Answer 55

send current directly to the heart

Question 56

how many mA can cause vfib

Answer 56

100-300mA in macroshock | 100mmA in microshock

Question 57

person contacts a 120V circuit with skin resistance of 1000 vs 100,000 ohms

Answer 57

``` 120V/1000ohms = 0.12 amps = 120mAmps 120V/100,000ohms = .0012 = 1.2 mAmps ```

Question 58

power is ___ in the OR

Answer 58

ungrounded

Question 59

electrical equipment in the OR should be ___

Answer 59

always grounded

Question 60

grounding of power and equipment provides

Answer 60

low resistance pathway for current during faults