Chapter 1 - Theory Of Electricity

Question 1

What is electricity?

Answer 1

The transfer of energy through the motion of charge-carrying electrons

Question 2

What is an electron?

Answer 2

The negatively charged particle in an atom

Question 3

If you had two conductors with the same amount of current and one of the conductors had a lower resistance than the other, which would get hotter?

Answer 3

Higher resistance would get hotter-more effort to go through, excites the electrons more and the molecular friction produces heat.

Question 4

Would a current-carrying conductor get hotter or cooler if you shortened its length?

Answer 4

Cooler-less area to distribute heat across.

Question 5

Which has less resistance, a conductor with a larger cross-sectional diameter or a conductor with a smaller cross-sectional diameter?

Answer 5

Larger, the more particles there are, the more friction occurs.

Question 6

What is the purpose of the insulation around a conductor?

Answer 6

Prevent electrical shock, prevent faults to ground and other conductors.

Question 7

What would happen to the insulation around a conductor if the resistance of the conductor is too high or the current flowing through the conductor is too high?

Answer 7

The insulation will become brittle and start to lose its integrity, and the gear will not last as long. If it gets hot enough, it can melt the insulation.

Question 8

When an electron is pulled away from the orbit of an atom, the atom becomes ______?

Answer 8

Ionized.

Question 9

What is the polarity charge of an ionized atom?

Answer 9

Positive.

Question 10

What makes some materials better conductors than other materials?

Answer 10

The structure of the atoms from which they are made; good conductors allow more of the free flow of electricity.

Question 11

If lightning is the flow of electricity, what is the conducting medium?

Answer 11

Air.

Question 12

In order for current to flow, there has to be a ____?

Answer 12

Conductive path made of conductive material.

Question 13

What prevents current from flowing where we don’t want it to?

Answer 13

Insulators.

Question 14

What is the likely consequence of running a power distribution system over full capacity?

Answer 14

It will produce too much heat, components like connectors, insulation will eventually or immediately deteriorate or fail.

Question 15

What is an example of an insulating material?

Answer 15

Rubber, glass, plastic.

Question 16

What is the inverse of resistivity?

Answer 16

Conductivity.

Question 17

Why is the direction of current convention opposite that of the flow of electrons?

Answer 17

Current convention was established before the knowledge that it was produced by the flow of negative charges.

Question 18

Is conventional current flow toward or away from the positive terminal of a battery?

Answer 18

From the positive terminal, through the battery, to the negative terminal.

Question 19

How do rubber gloves help prevent electric shock?

Answer 19

It is an insulator and inhibits the free flow of electricity.