gabrelov

Aerospace is a vast field which c

I'm considering doing aerospace engineering in the university
But my parents want me to do the actual study.
I want to know what it will be like if I do the aerospace engineering.
Is that a good career?

Aerospace is vast field which can be subdivided as aeronautical engineering and astronautical, with former dealing with aircraft opearating on earth's atmosphere while the later deals with those outside our atmosphere.

I've finished my degree in aeronautical engineering and its quite hard since it covers large are such as aircraft structures, propulsions, aerodynamics, materials and specially math which is quite annoying considering other couses focuses on just one side. I really wanted to get a course on astronautical but sadly no one offers that in my country so I'm planning to take post graduate degree on space propulsions.

In our country aerospace works on airlines as head of operations on aicraft maintenance and they get free trips abroad a week with their family, and is currently on demand due to our dwindling population. Almost all of them already got a round trip across the world.

If you wnat free world trip get aeronautical engineering and go to a airline or maybe manufacturing but if you want challenge take astronautical.

nice one I hate math before and even cursed calculus because I don't know what it is used for but now I love it more than any subject because I understood how it works and even while going to sleep I think of math.

All you have done is multiply two numbers together. You can think of any number as a map from the real line to the real line by multiplication.

 

Let me just stress that one has made a truncation here. That is after some finite number of decimal places we throw away all decimal places higher than this. In this particular case 1/3 is approximated by 0.3333.

 

It is however true that [math]0.\bar{3} + 0.\bar{3} + 0.\bar{3} =1[/math] (here I use bar to denote a repeating decimal.)

Yupz but if you are just a student and having an exam and the teacher tells you to show solution it is not practical to express something in decimal.

By the way many things are expressed in fraction instead of decimals in measurements such as the units of inches and so on.

 

 

If you imply that you divide and discard the rest, you are absolutely right, but in fact, aren't we just being lazy in writing, and still confusing divisions with fractions? Let's say we have to apply divisions and fractions to geometry. Kids are introduced to a rectangle, they are given the measurement of the area and of one side (width or length), and they have to find out the other side, without knowing any formula, making a very useful effort in finding the formula by themselves, this would be very educational. So, the length of one side of the rectangle is 4, but 4 what? 4 mm? Not necessarily, they can be 4 squared biscuits. The given area of the rectangle is 20 squared biscuits. Now the kids will easily align 4 biscuits to make one side, and they are left to wonder what to do with the rest of the biscuits (20-4=16), they will make a useful effort to align the rest of the biscuits, they don't discard or ignore any of them, until they finished the rectangle, and they will notice that the other side of the rectangle has magically only 5 biscuits. So, some of them will realize that initially they are simply dividing 20 biscuits into 4 rows, then they will have to ignore 15 biscuits to find out the length of the other side, some of them won't realize it, but that's not a problem, at least they are making a healthy effort to find out the formula, which is, divide the area by a given side, (20÷4=5x4) and discard (or ignore) 15. So are we just dividing 20 biscuits by 4 to find the other side of the rectangle? No, there is a discarding process. So, without being lazy, the formula should be written not with a division, but with a fraction, 20/4=5, and again the verb fractioning shouldn't be confused with dividing.

I get your idea that something is lost in the process of division but heres the thing. We surely know the rules of equality right, if we equate and use your equation, 20/4 = 5x4 it is not follwing the rules since if we balance the equation on both side the statement is not true, but if we remove 4 on either one side, it becomes true.

The problem here is that as children we are taught of to follow these basic rules and neglect to discover for ourselves how this things come up. You were right to say we became lazy and that is why many students fails in math because they don't understand the concept behind the equation and they just apply it without knowing its limitations.

Well it depends on the learning process we impart to them and math is only one way, there are others such music and playing instruments which will enhance our skills but we cannot force someone to learn something the way it should be, each one has its own way of learning, mabe for others they like shortcut method and so on. We cannot blame those who hate math since maybe they have other talents not related to math.

The quality of education I say is not good in some since advent of technology we rely on our calculators for computing unlike on old days where most of the formula we use today came from, they aren't lazy as before.

Another thing about a/b, in engineering this is very useful, suppose a/b is a nontermnating non repeating decimal, we dont want to get such number with so many digits. So we express it as fraction instead, such examples of it are pi and e which is really bad to express as decimal notation especially when doing accurate calculations. To lessen the error we let it stay as fraction until the we reach the end of the computation and then there we can express it in decimals.

For example: 1/3 = .33333..... adding 1/3 + 1/3 +1/3 = 1, but adding a rounded off 0.3333 + 0.3333 + 0.3333 = .9999 which is close but not equal to 1

Expression of a/b is very important specially in structural computation wherein a minute error can be catastrophic.

Why do we teach our kids that 6 ÷ 3 = 2? If I divide 6 oranges in 3, what I get is not 2 oranges, but 2+2+2, without subtracting 4 oranges. So why don't we teach 6 ÷ 3 = 2+2+2, 1÷2 = 0.5+0.5, etc etc? If I say "I would like a quarter of this cake", then I am not dividing, but I am dividing and subtracting, I am doing a fraction, 1/4. Don't you think divisions shouldn't be confused with fractions?

We can rephrase this as we have 6 oranges and there are three of you so we divide 6 oranges by three persons and you get 2 for each person.

It simply implies how many part will each person get.

1.) spec grav = density of substance over density of water (dimensionless)

2.) Use equation of state for ideal gas.

3.) Q = delta U + work

Additional

4) Newton's laws of motion

Now study this things I mentioned and you will get the answer

This are the basics of thermodynamics you should now this and study this well to be able to cope with much advance topics.

Study calculus very well specially integral since some problems have equation given and you will need to integrate correctly to get the answer. As our instructors remind us learn the basics and don't memorize formula but study where they came from so in case you forgot a formula you can derive.

 

If I'm understanding your process correctly, you're basically doing: [math]p_{n+1}=2^{p_{n}}-1[/math] for [math]p_1=2[/math]?

 

The statement is that "For [math]M_n=2^n-1[/math], if [math]M_n[/math] is prime, then [math]n[/math] itself is also prime." However, the converse is not generally true, and so the primality of the resulting numbers in your sequence will be uncertain. Your sequence will get very large very quickly, so you'll be testing extremely large numbers (though I may be misinterpreting your idea).

I'm sorry but i just got my idea from the theorem that if (2^n)-1 results in a prime then n is also a prime number.

Since Its just a theorem it may hold true for small values here are examples below and to note that n should always be prime to get also prime. Maybe its not true for bigger numbers so I'm gonna test it for bigger numbers.

2²-1 = 3

2³-1 = 7

2⁵-1 = 31

2⁷-1 = 127

The problem with my equation is that it may be simple but I think computer will not be able to run it when the number reaches so high such as thousands digits. If the computer stops processing there is nothing left doing but back to drawing board.

I think I will resort to mathematical equations again and derive and also to be able to get accurate answer.

Well, a proof could be derived from it. Since the two variables of U and L are prime(assuming), then it could try to prove that after a certain amount of numbers that are derived from the Mersenne formula that it will be prime or not prime.

 

For example, I used the new formula to get more primes than the Mersenne formula, however it took the increase of the exponent n for the 4 values to do so. After a certain while, you have to increase n in order to get more primes as you increase the size of the primes.

As I was reviewing I remembered that the exponent of 2 is prime so maybe I can create a simple program from visula basic C++ to run a non terminating exponent input on two and so on and forth. The program is relatively easy to make but the problem the processing capability of current computers. I'll test it this upcoming monday and ask some help from my younger brother to create the program.

It goes like these: (2^2)-1 = 3 which is prime by law and then substitute it back to (2^3)-1 =7 prime again, and so on and so forth until I reach the maximum possible prime number.

 

Cup of water upside down will pour the water on the floor, but the ocean stays on earth " for example."

Both examples here would not be possible without gravity and of coarse " the motion." IE, hand makes the cup tilt, earth causes people to rotate relative to the surface topology.

 

But this does not make any sense though, how can gravity work in both situations????????????

 

AGAIN:

 

Cup of water upside down will pour the water on the floor, but the ocean stays on earth " for example."

Both examples here would not be possible without gravity and of coarse " the motion."

 

 

If the world is rotating and one is like a tree on the ground would this be technically termed hanging upside down?

If so then the mind has no rule over " the physical reality" this is not QM here.

 

 

I mean the northern hemisphere of earth at some point must be at the bottom of earth's rotation so I am assuming somewhere like at night I should be feeling that I am at some type of angle, upside down right side up??

 

If I was walking on a basket ball I would know my movement due to my peripheral view of the basket ball, however earth is much much bigger than this...

 

I think there is something wrong here. Its not the mind nor our visual realities its the physical evidence of gravity having an effect on our " precognition" similar to QM....

 

 

Thats not physics at all, thats metaphysics

That's a good point and I read the link thanks sir

 

But aren't the laws of nature not concerned with what humans think and or perceive??

 

I have been told this before and in this circumstance I think I am finally understanding much about physics and science coupled with how the mind seems not to apply to physics and the physical laws of nature.

 

One cannot argue to see the physical fact that a cup pours water when it is tilted towards the floor, this is a physical fact that relies on gravity but oceans remain on the surface regardless of the rotation of earth...However, the moon does have effects on the ocean tides and so fourth..

 

So you say that G seems to have affects on the mind????????

Only on the surface???????????

 

9.8 m/s is G on the earths surface right??

 

Would this OP only hold valid on the surface of earth????

 

That is strange...

Same premise if one was on a hang glider.

 

But then when thinking about this, my OP would not matter

 

It would be then related to air pressure coupled with G on the earth's surface.

Seems like G has many virtual effects on nature even the mind???

Actually the upside down feeling is created by the brain, if you heard a news that a mice was born and raised in the ISS and then brought back to earth and placed in a aquarium and they were unable to dtermine which is up or down.

I will try to find the link and post it here

is the gravity pulling you outward the earth, nope its not its pulling you inward so you wont feel you are hanging. The force and pressure exerted to you by the gravity is normal to the surface thus you feel the gravity normal to the surface, you dont feel hanging because there is no gravity outside the earth so there is no force opposing the earths pull from you, Your brain is designed for that because you were born on earth. If you were not born here thus your brain will adjust to know what is up or down.

Collatz Theory is a newer form of mathematics(recent). I developed it originally to try to solve the Collatz conjecture, but I found more than I bargained for with Collatz Theory. For example, I have developed algorithms for the factorizations of composites consisting of two primes, the Mersenne hailstone sequences, hailstone series equations, and Collatz-Matrix equations.

 

The most helpful for this problem are the Mersenne hailstone sequences, hailstone series equations, and Collatz-Matrix equations. I am getting really close to finding some equation to easily prove a Mersenne number to be a prime. It will just take some more analysis.

Hopefully you get one and learn more from you, this will help me further if I take up post graduate degrees.

After reading the posts of this topic I try to distinguish between time and time.

Which of the following is true?: Note: So I don't open another topic (no need) because I think I can comment on which of the following:

I.1 Spacetime is a Cartesian system in which All that can exist exists in this spacetime?

I.2 Spacetime is Cartesian system with entities outside of it? Formally the spacetime being a mathematical set of equations which can constitute as a Sandbox in which you can perform some work, do some experiments? By who, if We were to be/live in Spacetime and not outside of it?

 

II.1 Spacetime treats time as a dimension without another time? In this case Spacetime can be considered static, from an objective point of view.

II. 2 Spacetime treats time as a dimension which recognizes another (discrete) time and in order to compensate is a process to add time to time (using the same time probably)?

 

Note: Spacetime: dimensions of/for distribution of matter.

One of the above is true or none of the above is true.

That is really hard considering we call time as time and it is integrated to 3 dimensional space thus its space time. But what we are really unsure of is that is there another time except for what we call time and what do we call it? As accordance to some theory we have time because we described and observed it but what if we don't have time, how do we measure things?

For me if you look at it time, it just a tool of measurement of how things change and by the law of conservation of energy, energy never disipitates but transforms in another form, so energy is timeless or doesnt have beginning nor end. Thus the change in energy form is what we measure. The same applies to us, we measure change using time, thus if there is nothing to measure we don't need time.

There is something happening and is relative to something thus we measure it by time but if a particle does not move change or do something we have nothing to measure from it and therefore it is not observed. In the universe we can only measure those observable things and beyond observable universe nothing possibly measuring of.

This way calculus was born, we want to determine the rate of change and so other laws was formed relative to time.

My question here is that not the existence of time but rather is it really possible to remove time or can we really stop time and what are its consequences?

The modified equation that you presented is actually more efficient than the Mersenne formula based on this sample:

 

While, in this set, 56% of all using the new method are prime while for the other it is 22%.

Well I applied Collatz Theory to Mersenne primes and have made some progress, but I am trying to find properties right now of Mersenne primes that separate them from the Mersenne numbers, which are numbers that just come out of the Mersenne formula whether prime or not.

Keep going I'm sorry I cant help you yet this time, I'm reviewing for my upcoming licensure examination for about 3 more months, maybe after the exam i can focus on what I want and hopefully take a PhD degree.

Hopefully we can apply other higher mathematics to solve that and produce another formula, for now I cannot study on that yet since our subject is too wide and we only tackled basics of the advance mathematics. I joined this forum so I could also learn from others here and I am happy I joined because some got my interest such as your problem.

so cool so what are its possible applications in actual life, sorry I'm not a physics student but I want to learn more on physics.

We apply physics in engineering adn we use the laws of physics in engineering but most of these are mathematical equations derived from the basic equation so for me its mathematical equations since we can form new equations from past equations.

Well one can try to find common relationships of each product when two Mersenne primes are added to 1 and divided by each other.

Its almost impossible to do divsion manually to check if its prime so others create their own programs which do the task for them. We only want to determine if the number would be a mersene prime. There are many other ways to do so. But what i wanted to do, is use only mathematical equations to prove that it is a prime number which is really hard considering almost all the mersene prime are computer generated.

We cannot depend solely on computer since it only follows set of instruction unlike human which is intelligent and can create new equations from almost nothing.

Using mathematica I haven't find any proof that it is composite, though I could be wrong. I am currently trying to use other methods(it is taking a while).

Are you looking for a mersene prime number. have you generated the answer to the equation, if its something like 1111111.......1111 there is a big possibility its a prime number.

By theorem:

Theorem Two: If 2ⁿ-1 is prime, then so is n.

Source:

http://primes.utm.edu/mersenne/

so first you need to determine if your exponent is a prime number

you would need to test it using the mersene form again such 2^n-1 = 257885161 and use logarithm and determine if n is whole number if not then there is a big chance its a prime number. By my calculations the value of n results in a whole number with a decimal value thus the number is not a result of 2 and its exponent.

Lets help one another in this forum if we suceed in getting another prime we win an award here and this site will be appreciated:

"GIMPS software was developed by founder, George Woltman, in Orlando, Florida. Scott Kurowski, in San Diego, California, wrote and maintains the PrimeNet system that coordinates all the GIMPS clients. Volunteers have a chance to earn research discovery awards of $3,000 or $50,000 if their computer discovers a new Mersenne prime. GIMPS' next major goal is to win the $150,000 award administered by the Electronic Frontier Foundation offered for finding a 100 million digit prime number."

Source:

http://www.mersenne.org/various/57885161.htm

ALTHOUGH the computer will generate a number as such for about a week and no guarantee of success, but there is nothing wrong for trying

It is probably a too long of title, but this question loomed in my mind. We all know that 3 dimensional geometric volumes have a finite size(unless told otherwise), and 2 dimensional shapes are made up of lines that are infinitely thin. However, 3 dimensional volumes such as cylinders are made up(theoretically) of 2 dimensional circles that are stacked upon each other until a given height, yet 2 dimensional shapes with lines that are infinitely thin are able to make up a certain height.

 

How is this possible? I mean the formulas for determining surface area and volume are based on these principles, though I could be wrong.

Mostly these formula were derived by integrating differential areas which are very small and we limit the dA into really small values such that it approaches almost zero but not equal to zero. then this minute area is then summed or integrated to create a big part and so on. This is used to determine volume of irregular shapes such as graphs given their equation.

Note: most integration produces errors or are not 100% accurate specially if the shape of the object is irregular and cannot be computed by cutting it to regular shapes. Errors which are neglected assuming it is small enough such that it almost approches zero in value which is not added to the actual value. This happens on such formulas on speed of sound and so on which errors are negligible that is why now we use actual apparatus and computer software to those calculations for us.

But actually you can compute it manually using other laws or theorems but would take you too long that is why calculus was made, imagine a box and sing a 2d plane for base calculation and adding almost all this infinitely small 2d planes if the area is "a" then we multiply by how many minute slice there is but consider this, the slice is almost zero in thickness let say .0000001 thick and add up all of it. That is very time consuming. Simple reasoning will tell you that when a 4x2x3 box is computed we just need to get the slice or the plane then multiply it by its thcikness to get the volume.

eg. A 4 by 3 box has a thickness of 2 so we just multiply two or if you want get small parts of the thickness and add it all up and you will get the same answer.

4x3 = 12 then the question is how many 12 areas are there in the box the answer is add all the infinitely small 12s using a given thickness such as 2 and you will get the answer.

So, I tried to determine if this is a prime number:

 

[math]2^{257885161} - 1[/math]

 

If this is a prime number, it will be the largest known prime, but if not then okay. Is there a quick way to tell? I tried dividing it by other numbers, yet after a long, long set of calculations I have found no factors yet(though I did this in Mathematica so it may be wrong).

obviously the 2^n is a composite number due to the fact it is divisible by two, unless we subtract 1 which gives a probability of it being prime or composite. Have you tried to get the answer sir two the equation and maybe we can apply laws of exponent and functions such as logaritmic to determine if there are possible factors or something that would make it composite.

Maybe people here would really help to find another prime number with mathematical eqautions to put this forums in the headlines.

 

I understand that not all uses it but we have follow unit consistency on most problems to get the answers correct since some old textbooks have their answers in slugs or some other units. Organizations were formed to make a standard unit for this units such as SI units. I am sorry we have different views but answer is just the same but of different units on most cases. But we in aeronautics community use slugs or either kg in the density and not lbs.

To add also it is important te get correct units and to be consistent to prevent miscalculations which is very critical for engineers specially on structural designs which even a minute error can cause catastrophic failure which we are responsible of. So if the given is in this unit we should answer the question on the same unit also which is the case on most textbooks.

 

Nonsense. I do understand where this nonsense comes from, but that doesn't stop it from being nonsense. A lot of schools now teach that the slug is the US customary unit of mass, and that pounds are a unit of force. This is nonsense. The slug is a non-standard unit used by some (but not all) engineers in the US. Other engineers are quite happy using the pound as a unit of mass and the pounds-force as a unit of force. The pound (Avoirdupois pound) is defined as 0.45359237 kilograms, exactly. The pound-force is defined as 4.4482216152605 newtons, exactly.

 

Weight is legally and colloquially a synonym for mass in the US. Better said, mass is a synonym for weight. Weight is a much, much older word than is mass. English has two words for the same concept for the same reason that the animals that provides pork are called swine. The Norman invaders spoke French, and their French words eventually became English words. It took a few more centuries after 1066 for the descendants of those Norman aristocrats to invade the merchant class. Mass didn't become an English word until the 15th century.

 

We in the technical community don't like it when the lay community pervert our own words. For example, "Evolution is just a theory." To avoid being hypocrites, we in the technical community should avoid doing the same to perfectly good English words such as weigh and weight. The supposed confusion between mass and weight is an invented controversy. As noted above, there is no confusion in everyday English. When your friend says he weighs 155 pounds (or 70 kilograms), fight back the urge to correct him. His usage is correct.

I understand that not all uses it but we have follow unit consistency on most problems to get the answers correct since some old textbooks have their answers in slugs or some other units. Organizations were formed to make a standard unit for this units such as SI units. I am sorry we have different views but answer is just the same but of different units on most cases. But we in aeronautics community use slugs or either kg in the density and not lbs.

Can you explain further what case are you into or what kind of crime happened or type of suspect you are looking for

If both time and 3 dimensions of space exist then time only holds those within fabric of space time, those outside it is no longer governed by time. Think of these, matter exists on the fabric of space time thus those not considered as matter is not affected by it.

Theory explains that time does not exist inside blackhole which is one example that time only governs those within the fabric of spacetime.

If you don't mind putting me some of those not affected by time are non existant such as "ghost", sorry, the only example i can give you. So judging by it, they do not age and they can travel at any moment since they are non existant and not subject to any law we know today. Spooky to think but science cannot disprove ghost just by existing laws because other laws may also exist on other universe or dimensions that is only waiting to be discovered.

Maybe one day we can prove it and we can finally see through those non existent and those outside the laws of physics.

Why are they Laughing at it, it is very important, I guess they do not know what are its uses. It is very useful to Engineers even though it is basic, it simplifies everything. Even Newton I think used it before to derive equations for calculus as well as leibnitz.

It says 3 times a number, we denote the number as variable x, so we multiply 3 to x and get 3x.

The next set words says "and 11", note and means addition or add and the first words says "the sum".

Is equal to 32 so we equate it to 32.

here it goes 3x + 11 = 32,

thus 3x + 11 - 11 = 32 - 11

3x = 21, dividing both sides by 3 you get 7

Substitute it to original equation to check your answer:

3(7) + 11 = 32 ----> 21 + 11 =32 -----> 32 = 32, correct