Recent content by cryptoguy

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    How Does Differentiability Imply the Existence of Partial Derivatives?

    Thank you for the response. What exactly is an "ith basis vector" though?
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    How Does Differentiability Imply the Existence of Partial Derivatives?

    Homework Statement A function f(x) : Rn ->R is said to be differentiable at point \vec{a} provided that there exists a constant vector \vec{c} = (c_1, ... , c_n) such that lim_(\vec{h} -> 0) \frac{f(\vec{a}+\vec{h}) - f(\vec{a}) - \vec{c}*\vec{h}}{||\vec{h}||} Prove that if the...
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    Total induced emf at different speeds

    it would... also increase? Yet if you move the coil faster towards the magnet, the instantaneous induced emf does increase, but the total time of movement decreases.
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    Total induced emf at different speeds

    if you move it faster... sounds like it'll increase
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    Total induced emf at different speeds

    Homework Statement Suppose you have a coil that is a certain distance from a magnet. Now you move the coil towards the magnet (until it is on top of the magnet) at a certain speed. Then you do the same thing only faster. Will the total induced emf be the same for both tries? Aka should the...
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    Interesting Electric Field and Spring Problemf

    Right, that's the answer for B because at the equilibrium position, the restoring force of the spring is equal to the electric force. That's why at equilibrium, Fnet is 0 so the acceleration of the block is also zero. For part A, consider the relationship between the potential energy of the...
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    Calculating normal force in a loop-the-loop situation

    Start with 2 free-body diagrams, 1 for the forces on the pilot at the top of the loop and one for the bottom. Keep in mind what force(s) provide the centripetal acceleration for the pilot at those points.
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    Understanding Motion: Solving Problems with Integrals and Acceleration

    Questions 9/10/11. If you know acceleration, can you find a function for velocity? And if you know the function for velocity, can you find a function for displacement? Keep in mind C (constants)
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    Rotational Motion and Gravity/Planetary Orbits review

    Don't calculate the inertia of a .4 kg particle using the formula for a long thin rod. Imagine that just the particle was revolving (held by a massless string for example). What would its' inertia be? Add this inertia to the inertia of the meter stick.
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    Rotational Motion and Gravity/Planetary Orbits review

    well for your first question, you're given a radius in part B. edit: for second problem you forgot to include the particle in calculating inertia
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    Using electric force to find the force of gravity

    yea that's what I was thinking, glad to help
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    Basic kinematics - conceptual questions

    1) Perhaps they wanted you to relate the distance between lights and the average speed of a driver to the timing of the lights. For example if the average speed on a street is 5 m/s, and the distance between adjacent lights is 100 m, they try to make sure that the light is green about 20 secs...
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    Using electric force to find the force of gravity

    if i understand the question correctly... the sphere is floating so like one force acts upwards and one acts downwards. If it is floating, what does that say about the magnitudes of the electric and gravitational forces? I'm not sure if what you did is right, but if I understand the problem...
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    The Electric Field of a Cylindrical Capacitor?

    For your first question, yes you use Gauss's law. Now imagine for a coaxial capacitor, the inside of it has a charge +Q and the outside has a charge -Q. Which of these (or both) contribute to the electric field in the capacitor according to gauss's law? Now with this, you should be able to...
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    What Force Does a Rod Experience in a Magnetic Field Setup?

    My bad, I kinda gave you the wrong link, try this http://en.wikipedia.org/wiki/Image:Rechte-hand-regel.jpg or the method I described (the link i gave you was for induced currents)
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