You don't have to be a rocket scientist

You don't have to be a rocket scientist 
We hear it all the time 
You know what I'm referring to 
I often wonder how the expression evolved and who coined this very esoteric phrase 
I sometimes wonder how to take it 
What is the proper context to which we should interpret it 
I guess it depends on the situation and how it is said 
I often wonder if it is an insult or just a way of saying it's not as difficult as we may make it out to be 
Sure it would be nice to understand the principles of jet and rocket propulsion 
The principles of physics that teach us about the forces of gravity and inertia and how they affect takeoff, the many stages of flight, re-entry and landing with regard to a rocket. 
There are so many factors that must be considered in the launching and successful return of a rocket, a shuttle, a space capsule or any flying device 
There are teams of scientists, engineers and physicists that work together in an organized setting whereby the flight and every aspect of the mission and the state of health of the astronauts are monitored by mission control 
Sometimes I wonder if our brain also has a similar system in which our every action is monitored and a response is made based on the stimuli present 
I believe our brains are only used to about 10% or less of what our true capability is 
I feel we don't give ourselves enough credit or we are afraid to take risks 
We fail miserably in math and science on the whole in our education system compared to Asia and Europe 
It is said that for most students they have a certain anxiety when it comes to pursuing math and science related ventures 
They just don't seem to feel comfortable and find it hard understanding theorems, theories, hypotheses, constructs interpretations and extrapolations of ideas and formulaic concepts 
Solving equations in x, y and z seems like an overwhelming task for most of us 
It doesn't take a rocket scientist or so it is said 
Understanding the concept of how rockets and rocket propellant work is for most a pie in the sky concept they never get to learn or ever truly understand 
It's not as complicated as you may be inclined to think as summarized in Newton's third law of motion 
Before discussing the third law we should already know the first two laws of Newtonian physics which were formulated by the great mathematician and physicist Sir Isaac Newton in his writings in 1687 explaining his reasonings and scientific explanations of motion illustrated in his 3 laws as formulated 
1. The first law simply states that every object in a state of rest or uniform motion tends to remain at rest or in uniform motion unless an external force is exerted upon it which is the law of inertia 
2. The second law states the relationship between an object's mass, it's acceleration and the applied force is the second principle of motion simply stated as the vector sum of the external force expressed as F= ma where acceleration and force are vectors that determine direction and change in velocity which is a function of time and one of the major principles of dynamics 

Another term I will throw out to you is momentum which is the quantity of motion of a moving body measured as a product of its mass and its velocity 

Now we must come to the whole basis for what rocket science is all about 

Newton's third law of motion 
We must understand basic concepts within this third law which simply stated is as follows 

A rocket must have forces exerted in equal and opposite direction 
Thrust is the first concept 
A rocket's thrust is based on its ability to expel mass backwards in a high speed in its combustion chamber creating a very hot gas at high pressure 
resulting in a force propelling it forward which is identified as the mass flow rate of the propellant which upon takeoff is multiplied by the exhaust velocity which is illustrated in Newtonian physics and identified as Newton's third law of motion 
Thrust is the equal and opposite reaction that moves the rocket 
Yes there is an equation that determines the maximum velocity a rocket can attain in the absence of any external forces which primarily is a function of its mass ratio and its exhaust velocity 
Although this is all sketchy to me now I did learn such principles in my engineering physics classes and for the benefit of those who may one day venture into this fascinating field of rocket science the formula goes like this 
Rocket equation: Vf = Ve ln (Mo/Mf) 
Vf is final velocity or maximum change in velocity 
Ve is the effective exhaust velocity relative to the rocket 
Mo is initial total mass including propellant 
Mf is the final mass after propellant is burned or fully utilized 
Ln refers to the natural logarithm function 
This seems like a lot to understand but it can be simulated with a simple Estes rocket kit that you can gain an appreciation for as I did in my studies 
In summary a rocket is primarily affected by 
1. Thrust from the engine system to get it to lift off into space 
2. Gravity emanating from celestial bodies while on its course into space and back to earth 
3. Drag which are forces exerted on the rocket resulting from atmospheric conditions in its flight 
4. Lift which is the power needed to get the rocket propelled into space with its launching engines 
So now with this little lesson you don't have to feel out of place when someone says 

You don't have to be a rocket scientist 

Emily Iannielli​ 
T-girl Angel​

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