what does propulsion mean?
595925
Spacecraft propulsion is used to change the velocity of spacecraft and artificial satellites, or in short, to provide delta-v. There are many different methods. Each method has drawbacks and advantages, and spacecraft propulsion is an active area of research. Most spacecraft today are propelled by heating the reaction mass and allowing it to flow out the back of the vehicle. This sort of engine is called a rocket engine.\n\nAll current spacecraft use chemical rocket (bipropellant or solid-fuel) for launch, though some (such as the Pegasus rocket and SpaceShipOne) have used air-breathing engines on their first stage. Most satellites have simple reliable chemical rockets (often monopropellant rockets) or resistojet rockets to keep their station, although some use momentum wheels for attitude control. Newer geo-orbiting spacecraft are starting to use electric propulsion for north-south stationkeeping. Interplanetary vehicles mostly use chemical rockets as well, although a few have experimentally used ion thrusters with some success (a form of electric propulsion).
779555
Hey! I just finished learning about active transport! The teacher confused me soooo bad! I had to have a friend in my class explain it to me. I would suggest going to google and typing in "active transport" and clicking on the news tab on the top. good luck with your project!
145032
The Breakthrough Propulsion Physics Program (BPP) is a research program which was funded from 1996 through 2002 by NASA, in the hope of studying various proposals for "revolutionary" methods of spacecraft propulsion which would require breakthroughs in physics before they could be realized, hence the name. Specific proposals studied under the aegis of the BPP included the Diametric drive, the Pitch drive, the Bias drive, the Alcubierre drive, the Disjunction drive, and the Differential sail.\n\nhttp://en.wikipedia.org/wiki/Breakthrough_Propulsion_Physics_Program
250852
Objective: to pilot through water and drive on land.\nStructure: The same as a boat with  external wheels. 2 engines,1 for the drivetrain(wheels) and 1 for the inboard/outboard motor(water)
392981
Is the speed at which it travels.
843918
Speed.\nSpeed is only concerned with how fast your travel, and not with the direction.  (One example for velocity, by contrast, is that you drive 1000 miles east and then 1000 miles west in one day, but your velocity is zero, because you are at the same position, and the same reasoning can be applied to acceleration, as well as force).
209188
An extention of the cell membrane which has the ability to move providing propulsion to the prokaryote
736848
Velocity is basically speed, normally a constant speed used when measuring extremely fast objects such as bullets. Acceleration is the rate at which an object increases speed. For example a car can accelerate from a standstill to 60mph in ten seconds
1173168
Space Transportation System
71420
A linear motor is essentially an electric motor that has been "unrolled" so that instead of producing a torque (rotation), it produces a linear force along its length by setting up a traveling electromagnetic field.\n\nLinear motors are most commonly induction motors or stepper motors. You can find a linear motor in a maglev (Transrapid) train, where the train "flies" over the ground.
779727
combustion? your question i super vague. the drive shaft applying torque created by the engine to the wheels which turn making the car move? you might want to be more specific. and if you look at wikipedia.org under combustion engine you might find what your looking for
109269
In space, because there is no air resistance or the like, thrust equals acceleration.  Also acording to newton's laws of motion an object in motion stays in that motion unless a force acts on it.  So if a rock is moving through space it will move with constant speed unless gravity or another force pulls or pushes it off course.  If a rocket constantly uses it's thrusters it would constantly accelerate until the force pushing it stoped.  I hope this helps!
909261
basically it is the amount of friction, caused by movement, or no movement. below is a GREAT link to explain. hope this helped!!!!\n\nhttp://hyperphysics.phy-astr.gsu.edu/hbase/frict2.html
54242
A change in a objects velocity produces acceleration.\n\nAcceration is a measurement of the rate of change of velocity, and is usually measured in "meters per second squared" or ms^-2.\n\nIf a car is travelling at 5 meters per second, and over a time of 5 seconds, increases its speed to 15 meters per second, it has accelerated at a rate of 10 meters per second over 5 seconds, or 2 ms^-2 (2 meters per second squared)\n\nHope that helps
555677
You are using the term "power" incorrectly. Power is the rate of production of energy. A jet may have enough energy, but it does not have enough power. A fully fueled jet may be able to burn all it's fuel with oxygen from the surrounding atmosphere to generate enough energy to make it to orbit, but it takes many hours to do that, and all the time it is being slowed by friction with the atmosphere. The shuttle burns all it's fuel in 10 minutes, and it carries it's own oxygen in a tank so it can operate outside the atmosphere. So even though they may have similar energy, the shuttle has far more power.
424514
The key is internal combustion.  If it has a fire in it, like a car engine or a jet engine, it is just that: an engine.  If its source of power is external, like an electric or hydraulic or compressed air motor, it is a motor.  That's the technical answer.  In practice, ignorance (as in lack of knowledge) causes many people to call engines motors.
131870
The term generally means "a kind of magic" or "magical power". Could it mean "an ability to run faster" or " ability to maintain speed longer by some unknown 'power' "?