Can someone explain the Hall effect thruster to me? I am in high school, and am doing a major research project on Russia. Part of that is a section on the space race, and ion engines/hall effect engines have come up several times. Unfortunately, Google and other searches on this site have turned up a whole lot of things that make no sense or do not pertain to space propulsion. Could someone please explain how a Hall effect thruster works, and why they seem to be so much more powerful than anything else we've sent into space, in terms that a high school student could understand?
** Note: I state more powerful because of a graph posted in a PDF by the air force. Because 
I do not have 10 rep, i cannot post the picture, but going to this link will bring up the PDF, the graph is on page 3.
 A: If you want to avoid Wikipedia, look at the following NASA resources:
Overview of Hall Effect Thrusters
Ideal Rocket Equation
The NASA overview is short and easy to read, so there's no need to re-explain how the thruster works. To expand on the discussion in this question, there are (at least) two circumstances where a Hall thruster is a much better choice than a chemical rocket. 


*

*When you need high precision stationkeeping: if you want to make precise adjustments to the orientation of a satellite, it helps to be able to control thrust in very small increments. This is a big challenge for chemical rockets, but Hall thrusters can easily adjust their thrust in milliNewtons by changing discharge voltage and/or propellant mass flow rate.

*When you need a high ratio of thrust produced to propellant used: Ion thrusters will usually outperform Hall thrusters here, but compared to chemical rockets the Hall thruster is still a much better choice. Read about Specific Impulse to lean more.
As you probably know, the weight of components is immensely important for space launch, so scientists and engineers make significant efforts to minimize weight wherever possible. For propulsion, if we can make efficient use of our propellant, then we don't need to carry as much of it, thereby reducing weight. The second link above shows the ideal rocket equation 
$\Delta{u}=v_{eq}ln(MR)$
where $\Delta{u}$ is the change in the spacecraft's velocity, $MR$ is the ratio of empty spacecraft mass (no propellant) to full mass (full of propellant), and $v_{eq}$ is related to the exhaust velocity of the propellant. So, suppose you have a propulsion system and you plan to use all of your propellant to get the biggest increase in velocity possible: you want to maximize $\Delta{u}$ for a fixed $MR$. As you can see from the equation, to maximize $\Delta{u}$ you must make the exit velocity $v_{eq}$ as large as possible. 
This is where the differences between propulsion systems become very clear. You can perform additional research as needed, but its not hard to find sources for the following typical exhaust velocities:
Liquid fueled chemical rocket:           under $5000$ $m/s$
Hall thruster:                           around $20000$ $m/s$
Ion thruster:                            around $50000$ $m/s$
When people tell you that Hall thrusters are "more powerful" than chemical rockets, they really mean that Hall thrusters give you more thrust for a given amount of propellant mass. In terms of thrust alone, chemical rockets win: There is no electric propulsion device in existence that can launch a rocket from earth's surface into orbit. Chemical rockets create high thrust by moving an enormous amount of propellant mass. Another good parameter for additional plasma thruster research is Thrust-to-power ratio ($T/P$).
A: Its not more powerful, its rather more efficient. Its basically a plasma device which produces plasma and ions are thrown out by mean of positive potential. Now the space craft will be charged positive over time, to compensate this a different component releases electrons hence maintaining charge. Ions are used as it is more heavy and gives useful thrust. its used for satellite re orientation and maintaining track. 
