When Ifirst thought of rocket propulsion it sounded very complex and hard to understand.I could not image that rockets could move in space where there is no friction.This concept is easy to understand now that I know escape velocity and conservation of momentum.These elements are easy to understand once the basics are learned.
In order to send a rocket into outer space we must escape our gravitational pull.Earth's gravity gets smaller and smaller as you get further from the center of the earth. Therefore, when an object that has been thrown up into the air stops acceding and starts descending, it is because of the gravitational field of the earth.
Lets say you throw an object up into the air and it does not return to the earth's surface. You have given the object escape velocity which is defined, as the minimum amount of velocity an object must have in order to escape the gravitational field of the earth.As told by the NASA Explorer's articles "Escape velocity requires an object to propel itself with enough speed and thrust to break through a barrier".
In order to break through this barrier, it requires that an object to be traveling at an enormous speed of an estimated value of 25,000 miles per hour.Since we have not figured out cold fusion, we need a lot of fuel to send an object into outer space.On the space shuttle the orange colored tank called the external tank is full of oxygen and hydrogen which propels the space shuttle in to outer space. The space shuttle has two big rockets on the side called simply the solid rocket boosters. These are for the sole purpose of getting the space shuttle through the earth's gravity.On the television show, Speed Without Limits, they compared the solid rocket boosters to, two big firecrackers with 3,300,000 lbs of thrust.
Here on earth, what makes a car go is not just the engine itself, but the friction force applied by the…