Recent content by airbuzz

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    Should the U.S. store its Nuclear Waste in Nevada's Yucca Mountain?

    Ehi men, do you know how much it costs to put something in orbit? Actually it is about 10000 to 50000 Eur for each Kg you want to take up. And you leave it in a LEO (Low Earth Orbit) or in the best case ine a GTO (an elliptic orbit with perigeum LEO orbit and apogeum GEOstationary...
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    How Do Dimples on Golf Balls Affect Aerodynamics?

    I think you´re right...
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    Sliding Box: Constant Speed or Increasing?

    Newton´s law: F = m a If you have a force (sum of all forces in the system, also friction) that is not zero, you always have an acceleration...
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    A basic electrical question, but i can't work it out.

    if everything is in parallel, no matter what you put, the voltage in the parallel is given by the voltage of the dc battery so the current in the resistor is V/R. In real word however, each battery has an internal resistor in series and a current generator has a resistor in parallel, so you...
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    POLL - geographic location of our members

    Male, Italian, working in Germany
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    Could Nuclear Thermal Rockets Revolutionize Space Travel?

    Well, nobody here talked enough about Nuclear Electric Propulsion (NEP). Nuclear Termal Rockets (NTR) are a very good possibility to low down the costs to go from ground to space, but are at all not good for interplanetary missions. I explain: Chemical propulsion can have a maximum specific...
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    What is the Magnetic Field Between Parallel Plate Electrodes?

    it is a TeX command to write theta in that way. \theta \Rightarrow\,\,\theta \vartheta \Rightarrow\,\,\vartheta
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    Problem on block sliding on a wedge

    For the second question I don´t understand if m must not move respect a fix coordinate or respect to the wedge...
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    Problem on block sliding on a wedge

    is there no friction? in this case the interaction force between the block and the wedge is the normal vincular reaction, that is equal to the normal compnent of the block weight that is: N=mg\cos\alpha where alpha is the lower angle of the wedge. So the horizontal force between the wedge and...
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    Can You Solve These Challenging Friction Problems?

    Then, to find the speed upon emerging you must substitute the sand length [15 m] in the x formula, and find the time you need to emerge from the sand. When you find this you substitute this t in the speed formula (\dot{x}) and find the emerging speed. And you hav finished all the problems.
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    Can You Solve These Challenging Friction Problems?

    Second: you must use the Newton´s law. Acceleration equals force so that if x is space then speed and acceleration are \dot{x} and \ddot{x} where the dots mean derivation in time. If \mu is the friction coefficient the Newton´s law gives m\ddot{x}=-\mu mg\rightarrow\ddot{x}=-\mu g where g=9,81...
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    Can You Solve These Challenging Friction Problems?

    First: if you use breaks then you have that the maximum static force is given by \mu N\cos\vartheta and the parallel to street component of the car weight N is N sen\vartheta You start to move when the second is bigger than the first, so the maximum angle is given by Nsen\vartheta=\mu...
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    Help 2-dimensional motion, with a bounce

    You should find the launch angle with the arctan of h/(x/2). If you have no air drag the landing angle is the same. So, if you find the angle you can find the x and y velocities when the ball lands. If there is no friction the x velocity remains the same. To find y velocity you must know if the...
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    What is the height at which the small object loses contact with the spheroid?

    you must write the dynamic equation of the ball on the spheroid dividing normal and parallel forces to the surface. When the centrifugal acceleration equals the normal force to the surface made by the normal component of the weight of the ball then the small object leaves the spheroid
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