Recent content by Hepic

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    Find frequency response and circular frequency

    Homework Statement We are given that system of 1st grade 1/2 * dy(t)/dt + y(t) = x(t) 1) We need to find frequency response { H(w) } 2) We need to find circular frequency -3dB 3) We need to find the absolute value of H(w) in dB for frequency f = 3/π Hz 2. Homework Equations (log is always...
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    Watching Hawks in Nature: Is My Thought Correct?

    I asked a guy also,about air resistance. I asked him,why air resistance becomes smaller when we minimize our area,and he answered me that it is about fluid mechanics. Also he told me that it is a bit complicated and not so straightforward as in classic mechanic. Is that true?
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    Watching Hawks in Nature: Is My Thought Correct?

    Or maybe it is not about pressure,but it is become closing its winger the hawk,the same force as before now pushes the hawk in lesser area. So the whole force is lesser? (air resistance with few words)
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    Watching Hawks in Nature: Is My Thought Correct?

    I see. So we can suppose that we have two forces: F1 is hawk's force and F2 air's force ? And after to suppose that F1 stays the same,but F2 becomes smaller cause pressure of air becomes smaller? Am I wrong again or no?
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    Watching Hawks in Nature: Is My Thought Correct?

    I am in nature,and I am watching hawks motion. I knew it before and saw it live now,that when the hawk see the animal that wants to eat,close its feather to go faster. I made a thought,and I would like to tell me if it is correct or anything is missed. I think that closing its feather,make air...
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    Understanding Why C/d = pi is a Constant

    I found it guys. The proof use similar triangles etc... Thanks for your time !
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    Understanding Why C/d = pi is a Constant

    Lets say that "d" is diametr of a circly,and C is the perimetr(length). Why C/d = pi (3.14) is a constant?? I know the proof of archimides with poligons,from which found the value of pi,but how we know that C/d is always equal with a constant that we named as π=3.14; Thanks !
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    Did Humans Go to the Moon? A Debate

    I have seen some documanters,and I have talk with some people about this issue: "Did human go to Moon ?". Many people supports that never we went to Moon,and they have some logic arguments. Other people support,that something so big...can not be fake,so we went to Moon for sure. What you...
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    Probabillities in the World Cup

    I was watching yesterday my county(Greece) in international cup,and I thought something about probabillities. Let's say, that two football games take place the same time. In the first game, the team that we want to win has 30% to win,and in the second game the team that,we want to win has 20% to...
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    What is the Lorentz Transformation Equation and its Use in Relativity?

    Are you sure there is constant "k"? Cause I read today Lorentz,and I saw nothing about that? Also if there is,then what is the value of "k" ?
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    Lorentz transformation And Einstein's Laws.

    So,that what I call eistein's law,is when two phenomena,are located at the same location(dx=0) ?? Thank you by the way!
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    Lorentz transformation And Einstein's Laws.

    The einstein law,will not give me correct answers??
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    Lorentz transformation And Einstein's Laws.

    So,for example we have two humans. One in Earth and one in spaceship. To count the difference of time that they count,which law is the correct? Both,counts the time of standing,relative to the time of moving person.
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    Lorentz transformation And Einstein's Laws.

    To=(time of moving object.) T=(Time of standing object.) ^=power of number. sqrt=square of number.(x^1/2)Law of einstein say: T= To / ( sqrt( 1 - u^2/c^2 ) ) Lorentz law say: T= (To + u*Xo/c^2) / ( sqrt( 1 - u^2/c^2 ) )Why there is difference?? Is for other things?? I thought is for the same...
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    Proof of E=h*f: Energy of Photons

    Thank you for your answers,everybody!
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