# Electron Versus Conventional Flow

## Discrete Semiconductor Devices and Circuits

• #### Question 1

In this electrical circuit, trace the direction of current through the wires:

• #### Question 2

Show which directions these free-floating ions would move, if exposed to an electric field of the polarity shown:

Note: the “H ” ion is a positively charged hydrogen atom, while the ÖH” ion is a negatively charged hydroxyl ion.

• #### Question 3

Label the directions of both electron flow and conventional flow in this simple circuit:

• #### Question 4

In metallic conductors, the dominant carriers of electric charge are free electrons, which of course are negatively charged. Are there any examples of electric conduction where electric charge is carried by positively-charged particles?

• #### Question 5

Explain, in your own words, how we came to have two completely opposite notations for labeling the direction of electric current. What historical events led to this confusion, and why does it still exist today?

• #### Question 6

When you see an electronic device symbol such as any one of these, which direction do the symbols’ intrinsic arrows represent, electron or conventional flow?

• #### Question 7

Two people are debating electron flow versus conventional flow. One of them says that the you will get different results predicting polarity of voltage drops in a resistive circuit depending on which convention you use. The other person says the convention for labeling current does not matter at all, and that the correct polarities will be predicted either way.

Which of these two people is correct? Explain why, and give an example to prove your point.

• #### Question 8

Suppose a person is more familiar with conventional flow notation than electron flow notation. If this person find themselves in a situation where they must draw the direction of current according to electron flow notation, what advice would you give them for making the transition.

• #### Question 9

A Cathode Ray Tube, or CRT, is the heart of an analog oscilloscope. It functions by aiming a focused beam of electrons at a phosphorescent screen, causing light at the point of impact:

What style of current notation (electron or conventional) would best suit a description for the operation of a CRT?

• #### Question 10

In the following graphic, you will see the directions of currents labeled with arrows for each semiconductor component. Some of these arrows are pointing in the direction of conventional flow, while others are pointing in the direction of electron flow. Determine which convention is being used to label currents for each component (note: I have only used one convention for each component - I have not mixed conventional and electron flow while labeling multiple currents on the same component!).