Recent content by physikamateur

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    On length contraction (Special Relativity)

    The equatorial radius (a) of the prolate spheroid would be contracted by a factor of γ. (i.e a=r/γ). Therefore the volume of the sphere is V=4∏(r^3)/3 and the volume of the prolate spheroid would be V'=4∏(r^2)b/3(γ^2). Finally, taking the volume of the sphere and divide it by the volume of the...
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    On length contraction (Special Relativity)

    Homework Statement Show that the length contraction deforms a sphere in motion to an oblate rotational ellipsoid whose volume decreases by a factor of γ (gamma) Homework Equations x=x'/γ v=4∏r^3/3 (volume for sphere) v=4∏(a^2)b/3 (volume for prolate and oblate spheroid) The...
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    On (pentagon shaped) electric field question.

    Darn, can't upload the diagrams. I've uploaded it on my random blog. Go to www.kcsuploads.blogspot.com and see pentagon diagram. Sorry for any inconvenience caused
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    On (pentagon shaped) electric field question.

    Homework Statement Four particles, each having a charge q are placed on the four corners A, B, C, D of a regular pentagon ABCDE. The distance of each corner from the centre is a. Find the electric field at the centre of the pentagon. Homework Equations E=q/(4∏ε0)(a^2) where k=1/4∏ε0...
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    On a silly electric field question.

    Understood. But in finding the electric field at O while working the equations, do I consider a ficticious charge to be present at O say q1 so that E(A)=[((k)(q)(q1))/(r^2)]/(q1) and the q1 cancels off to give E(A)=(kq)/(r^2) ? Moreover pertaining to the initial question, the electric field at O...
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    On a silly electric field question.

    Correction: What I meant to say was "Honestly, if particle A has a charge of +q and if B has a charge of -q, then the electric field at O ought to be zero as they cancel each other out."
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    On a silly electric field question.

    Homework Statement This question is actually the simplification of a more complicated one. A particle of charge +q is placed at a point A while another particle of charge +2q is placed at B, a distance of 2r to the right of A. The midpoint between the distance is denoted as O. What is the...
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    What Happens to Atoms When You Tear Paper?

    I know this might sound silly, but I always wonder what happens when you say, tear a paper. Do I actually rip the atoms of the paper ? If so wouldn't nuclear forces be rather weak ? The question also reminds me of hardness. What makes an object hard ? is it the arrangement of atoms ? or to be...
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    On non linear resistor and how to calculate a fixed resistor.

    By I=0.05V^3, when I=0.40A, V=2V. Hence voltage drop across the fixed resistor is 9-2=7V. Therefore by V=IR, 7=0.4R, Therefore R=17.5 ohms Am I right ?
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    On non linear resistor and how to calculate a fixed resistor.

    Homework Statement The current in amperes through a certain type of non-linear resistor is given by I=0.05V^3, where V is the potential difference in volts across the resistor. This resistor is connected in series to a fixed resistor and a constant voltage source of 9V is connected across...
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    Solve Confusing Freight Transport Problem on Titan

    Homework Statement Freight transport on Titan is mostly by ship, with three types of ship called pangs, quizzers and roodles in common use. All three ships have the same shape and design but differ in size. The cargo capacity depends on the hold volume, while the number of crew required is...
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