Chapter 10- Electricity

Question 1

Electricity

Answer 1

Change in potential energy caused by flow of electrons from high concentration to low concentration

Measured in coulomb

Question 2

1 coulomb=?

Answer 2

1.6^19 electrons

Question 3

Coulomb’s Law

Answer 3

Like charges repel, opposite charges attract

The magnitude of electrostatic force of attraction or repulsion

Question 4

Volt (V)

Answer 4

Unit of electrical potential

The electrical gradient of charges that could potentially flow

Question 5

Current (I)

Answer 5

Rate of flow of an electrical charge through a conductor (copper wire)

Measured in amperes

Question 6

Conductors

Answer 6

Low resistance to flow.

Charges can easily move

Question 7

Insulators

Answer 7

No electrons are easily moved

Resist flow of electricity

Question 8

1 ampere=?

Answer 8

1A=1C/sec

The flow of 1 coulomb per second

Question 9

Ohm’s Law

Answer 9

Measures resistance to electrical flow

V=IR

Question 10

Electric circuit

Answer 10

The closed path through which a charge flows

Question 11

Direct current (DC) circuit

Answer 11

Current flows in one direction only

Question 12

Alternating current (AC) circuit

Answer 12

The current reverses it’s direction in a periodic fashion at a set frequency, usually 60 Hz

Question 13

Short circuit

Answer 13

A situation in a circuit where the normal resistance of the circuit is bypassed by a low resistance path resulting in a large current

Question 14

Series circuits

Answer 14

When batteries or resistors are connected in a series, the voltages and resistances are added

Question 15

Electrical power

Answer 15

The product of volts and amps

Measure in watts

P=IV

1watt=1V•A

Question 16

Electrical shocks are possible from?

Answer 16

Stray (leaky) capacitance and inductance (transfer by electromagnetic waves)

Question 17

High frequency current

Answer 17

Does NOT excite contractile tissue and does NOT cause cardiac dysrhythmias

Question 18

Ground fault circuit interrupter (GFCI)

Answer 18

Used in circuits near water sources.

Immediately disrupt the flow of current on the circuit if a change in current is detected

Question 19

Isolation transformers

Answer 19

Rely on magnetic inductance to transfer a current from the grounded electrical system to an ungrounded secondary system WITHOUT THE 2 systems physically contacting

Used in OR

Question 20

3 sources of shock

Answer 20

1. Direct wire contact w/ metal casing due to insulation damage
2. Inductance by electromagnetic field w/o contact
3. Stray capacitance from the buildup of electrical potentials with an AC circuit

Question 21

How to prevent electrical shock

Answer 21

Polarized plug
Three-pronged grounded plug
(Current will flow through 3rd prong instead of your body)
Ground fault circuit interrupter
Isolation transformers
Line isolation monitor