Class+Definitions+7th

=Propulsion : to push forward or drive an object forward. =

 The word is derived from two Latin words:

 * **//pro//** meaning before or forwards
 * **//pellere//** meaning to drive

 Examples:
>
 * 1)  A propulsion system is a machine that produces [|thrust] to push an object forward.
 * 2)  On airplanes, thrust is usually generated through some application of Newton's [|third law]of action and reaction.
 * 1) A gas, or **working fluid**, is accelerated by the engine, and the reaction to this acceleration produces a force on the engine http://www.grc.nasa.gov/WWW/K-12/airplane/bgp.html

=**Thrust** is a reaction force described quantitatively by Newton's Law.= When a system expels Second and Third Laws or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system

Apogee //-noun//:the point in the orbit of an object (as a satellite) orbiting the earth that is at the greatest distance from the center of the earth  ; //also// <span class="sense_content">**:** the point farthest from a planet or a satellite (as the moon) reached by an object orbiting it — compare [|perigee] French //apogée,// from New Latin //apogaeum,// from Greek //apogaion,// from neuter of //apogeios, apogaios// far from the earth, from //apo-// + //g&emacr;, gaia// earth Date:1594<span class="sense_break"><span class="sense_content"> <span class="sense_break"><span class="sense_content"> http://www.merriam-webster.com/dictionary/apogee

aerospaces//(noun)-//<span class="sense_break"><span class="sense_content">pace comprising the earth's atmosphere and the space beyond
Date:circa 1958 http://www.merriam-webster.com/dictionary/aerospaces

<span class="sense_break"><span class="sense_break"><span class="sense_label start">Altitude(noun)- <span class="sense_content">a high level (as of quality or feeling) <the //altitude////s// of his anger> <span class="sense_break"><span class="sense_label start"> <span class="sense_break"><span class="sense_break"><span class="sense_content"> plural   http://www.merriam-webster.com/dictionary/altitude