Recent content by vivekrai

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    Finding group velocity and Phase velocity

    Bump Please!
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    Comp Sci Understanding Newton's Method in C++

    while(fun2(a)<0.001); Are you sure about this?
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    Finding group velocity and Phase velocity

    Homework Statement A wave packet in a dispersive medium is given as : y(t) =cos(x-5t)cos(.2x-.4t)cos(.1x-.2t) Find group velocity and phase velocity for the wave packet. Hence plot w-k variation for the calculated values. 2. The attempt at a solution We know that for the wave, Vg = dw/dk and...
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    How Cell Phone Batteries Calculate Remaining Charge

    I do not know to which section this question belongs correctly. The question is : How does our cellphone calculates or knows the percentage of battery left?
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    Solving the Eletrodynamics Basic Homework Statement

    What if It is a spherical shell with different mass densities along it surface. I mean shape is symmetric but the mass distribution isn't?
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    Solving the Eletrodynamics Basic Homework Statement

    He said the it isn't valid for non-symmetric objects. Here the object though has mass non uniformly distributed, is symmetric. So Is it or is it not?
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    Solving the Eletrodynamics Basic Homework Statement

    Please note that in the question the gravitational field has been represented by E rather the Electric field. If already noted, then please ignore. He has this to offer as explanation : The gravitational field(due to the shell) inside(anywhere) inside a symmetric shell=0. This is not valid...
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    Solving the Eletrodynamics Basic Homework Statement

    Homework Statement In non uniform spherical shell of mass 'm' and radius R (here E is gravitational intensity) which of the following are wrong; (A) E = 0 (r<R) (B) ∫ E.dS = 0 on any closed surface inside the shell (C) E can not be zero at any point inside the shell (D) Gravitational...
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    What is the acceleration of an electron in an electric field?

    I feel that you approach is correct. It's a kinematics type problem only. Some where you might be making mistake in units.
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    Dynamics and F=ma, where a is 0

    What is that attempt? You seem to have learned things in way too hurry. First draw the FBD of the block. See what are the forces acting on it. How can it's acceleration be put to zero etc.,
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    Does it matter if a charge (unknown) placed at infinity

    Homework Statement Does it matter if a charge (unknown) placed at infinity w.r.t to one known charge be called positive or negative? Homework Equations - The Attempt at a Solution -
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    How Does the Tension in a Cord Between Two Masses Compare to an Applied Force?

    Let The Tension in the connecting cord of P and Q be T. Now draw the FBDs. I think the answer should be C.
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    Gravitational motion problem, degrees along orbit

    Okay. Thanks for letting me know. Then probably you can measure 60 degrees arc of length with some maths of hyberbola at hand.
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    Gravitational motion problem, degrees along orbit

    You didn't get any orbit by solving a, that's why you could not do (b). I think you should re think for part (a).
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    Maximum Static Force before Blocks Slip

    Try to imagine by sitting on the lower block. What you see? Where should the force act?