Recent content by AdrianGriff

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    How exactly does a turbine convert mechanical energy into electrical?

    Well the "goal" is to attempt charging a 3.7V 350mAh battery with a turbine with a blade diameter of approx. 12mm. Obviously this is very small, so I'm curious if creating a teeny tiny generator would be viable.
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    How exactly does a turbine convert mechanical energy into electrical?

    I am referring to wind turbines with relatively lower speeds on a much smaller scale. And I am familiar with induction motors/generators and the like, but I am curious as to if there are any differences or more efficient methods for a generator in a wind turbine that can be used on small scales.
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    How exactly does a turbine convert mechanical energy into electrical?

    I understand that the turbine drives rotational motion of a low and high speed shaft which rotates within the generator, but how exactly, and with what components/materials does this create electrical energy? Is there a minimum required rotational speed or torque required to generate...
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    Flight Path Angle and Velocity During Atmospheric Re-entry

    I noticed that your units for ##ξ## were not ##ft^2/s^2## are they not supposed to be that way? From the equation for ##ξ## I see no reason why both units distance and time should not be squared. Also, when you did the 'sanity check' you said Escape energy = 1/2mv^2 and that you got an energy...
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    Flight Path Angle and Velocity During Atmospheric Re-entry

    It is not intending that 100 nmi is lower than the entry altitude, it is asking what the velocity and flight-path angle were previously when higher in orbit assuming it is on an entry path back to Earth.
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    Flight Path Angle and Velocity During Atmospheric Re-entry

    Well, my first instinct to attack this problem is to find both the Specific Mechanical Energy ##ξ## and Specific Angular Momentum ##h##. I did this using the velocity ##v = 25,000 ft/s## and ##r_{entry} = 300,000ft + 20,902,230ft = 21,202,230 ft##. $$ξ = \frac {v^2} {2} - \frac {μ} {r}$$ Where...
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    Flight Path Angle and Velocity During Atmospheric Re-entry

    I essentially found the specific angular momentum of the vehicle when it enters the atmosphere (ie 300,000), so h = rv*cos(flight-path angle), and then equated that to h at the altitude of 100 n mi. Since I need both the veocity and flight path angle at the altitude of 100nmi, I solved for the...
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    Flight Path Angle and Velocity During Atmospheric Re-entry

    A space vehicle enters the sensible atmosphere of the Earth (300,000 ft) with a velocity of 25,000 ft/sec at a flight-path angle of -60 degrees. What is its velocity and flight-path angle at an altitude of 100 nautical miles during descent? (Assuming no drag or perturbations, two body orbital...
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    I I want to see how d/dt (-mu/r) = mu/r^2 * v

    Does treating ##\mu## like a function, and using the chain rule also create the same output? As G, M, and m are all constants and would all derive to be equal to zero? Or must it remain solely as a parameter? Thank you a lot though :)
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    I I want to see how d/dt (-mu/r) = mu/r^2 * v

    Thank you :) However the only ambiguity I can feel for here is that is ##\mu## not a function? If ##\mu = G(M+m)## is that not considered a function during derivation?
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    I Questions About Acceleration and Jerk in Orbits

    Could you invest a bit of time into helping me understand this question? I don't mean to ask too much, but this is a pestering and burning question. Perhaps it is too out of my grasp (I am only 18, still in high school), but regardless, I would like to know why it is the way it is. I could send...
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    I Questions About Acceleration and Jerk in Orbits

    Well this is only a small step in deriving the conservation of mechanical/orbital energy, ##ξ## provided in The Fundamentals of Astrodynamics by Roger R. Bate, But the only extra information that I can think that would be important is that: 1) The orbit is perfectly circular 2) There is no...
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