Recent content by GiuseppeR7

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    What is the most aerodynamic shape for minimizing air resistance?

    If you are really intersted in this topic just get Fluid Dynamic drag by Hoerner :)
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    What is the most aerodynamic shape for minimizing air resistance?

    typically the "most" aerodynamics shape sis dictated by constraints...and finding it is very difficult (this is why aerospace engineers are involved with it), with no constraints a point have zero drag so...a point is the answer.
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    What Is the Total Angular Velocity of a Disk in a Robotic Arm?

    I have the "robotic arm" shown in figure...the angular speeds w1, theta, w3 are given...they are asking me to find the total angular velocity of the disk. Can anyone explain me (conceptually) 1) what do we mean by total angular velocity of the disk and 2) how to find it...i have not understood...
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    Graduate Unable to understand vector derivative

    it was using a confusing notation! :p
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    Graduate Interesting Electrodynamics Problem

    Suppose you are calculating the Poynting Vector of a point charge near a magnet...you can discover that the energy flows in circles around the magnet, from where this angular momentum come from?
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    Graduate Unable to understand vector derivative

    Thanks for the reply...a bad paper misleaded me on this topic!
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    Graduate Unable to understand vector derivative

    Hi guys...i'm having a bad time understanding the concept of vector derivative with respect to different frames. Suppose i have the vector displayed in the picture, the frame A and B are in motion with respect of each other, i can understand the concept of the derivative of the vector R in the...
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    Undergrad Gradients vs. Partial Derivatives

    partial derivatives are "limits" meanwhile the gradient is an operator.
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    Graduate What is the asymptotical expansion of Sin(x^-1)?

    Ok, thanks for the reply...for example...how can i find the asymptotic series for Ln(1/Sqrt(1 + x)) ?
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    Undergrad Derivatives in Action, Change in radius per time of circle.

    The first formula is wrong: A=2 Pi r(t)^2 dA/dt= 2 Pi 2 r(t) (dr/dt)
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    High School What is the relationship between electric potential and potential difference?

    Since the electric field in stationary situation have some properities you can introduce a function P(x1,x2,x3) called potential function for which: dP(x1,x2,x3)/dxi=Ei where Ei is the component of the electric field in the direction of the unit vector xi (x1,x2 or x3) the potential difference...
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    Undergrad A theoretical question about forces

    No, it' not correct. Supposing the bed was like a clean table with some kind of oil to eliminate the friction between the body on it and the bed the force on the head is going to be close to zero or zero (idealy).
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    Undergrad Fitting a (Very) Large Random Number To A Formula

    https://reference.wolfram.com/language/tutorial/ManipulatingNumericalData.html https://reference.wolfram.com/language/tutorial/CurveFitting.html
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    Undergrad How Does the Chain Rule Explain Acceleration in Terms of Distance?

    some times you may want to realize that V is a function of S that is of course a function of t V=V(S(T)) so taking the derivative (with respect to t) you are going to obtain: a=(dV/dS)V there is nothing deeper than this! The general chain rule is: having g=g(h(x)) g'=g'(h(x))h'(x)
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    Undergrad A question about "semantics" ["Rational Mechanics"]

    Hi guys...i was wondering what is "Rational Mechanics"? and is it the same as "Analytical Mechanics"? Which book do you guys suggest for studying this stuff?