Voltage and Current

Question 1

When the number of protons equals the number of electrons, the atom is electrically _________.

Answer 1

neutral

Question 2

The law of electrostatics states what?

Answer 2

Question 3

A simple electric circuit has what three requirements?

Answer 3

Voltage source
Conductor
Load

Question 4

The voltage source is represented by what letters?

The battery is represented by what schematic symbol?

Answer 4

The voltage source is represented by the letter (E) or (V)

Question 5

Current flows in a simple circuit when a path is provided for the current to follow. The path current follows is called what?

Answer 5

conductor

Question 6

Current is represented by the letter ?

What direction does current normally flow?

Answer 6

Current is represented by the letter ( I ).

Question 7

A simple circuit needs a load. The load can be any device as long as charge flows through the device. A load provides resistance to current. The resistance provided by a load is represented by what letter?

Answer 7

The resistance provided by a load is represented by the letter (R).

Question 8

When 6.25 billion billion electrons pass a given point in 1 second, the value of current is equal to what?

Answer 8

1 ampere

Question 9

Electrons always move toward a ______ charged atom.

Answer 9

Electrons always move toward a positively charged atom. For this reason, electron flow is always from negative charge to positive charge.

Question 10

______causes electrons to flow, and the flow of electrons is called _____.

Answer 10

Voltage causes electrons to flow, and the flow of electrons is called current.

Question 11

What are three major factors and one minor factor that affect the conductivity, or the free movement of electrons in a conductor

Answer 11

Major Factors

1. Specific resistivity of the conductor. (Silver copper, gold, aluminum etc.)
2. Length of the conductor.
3. Cross-sectional area of the conductor.

Minor Factor

1. Temperature coefficient.

Question 12

Although not the best conductor, _____ is most commonly used due to its low cost and ready availability.

Answer 12

Although not the best conductor, copper is most commonly used due to its low cost and ready availability.

Question 13

There are times when we do not want current to flow. For those times we use materials called ______.

Answer 13

There are times when we do not want current to flow. For those times we use materials called insulators.

(Glass, paper, rubber, plastics)