Recent content by mustafa

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    MSc. Bilogical Sciences-BITS,Pilani

    BITS Pilani is great. If you are interested in Biological Sciences, you should go for it. However, you have not specified other options available to you. You must select, what you think is the best available option to you.
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    Discovering Solid State Electronics: Devices and Their Applications

    Basicaly solid state electronics is related to the property of semi-conductors like silicon, germanium in pure as well as doped form. Metals show linear voltage-current characteristics in accordance with the Ohm's law, whereas semi-conductors with different type of doping have different...
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    What superhero do you most closely identify with?

    Dexter! Always messing up things.
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    Graduate Construct Approximate Circles with Straight Edge and 20% Accuracy

    Hey, I am able to construct an ellipse. Using BicycleTree's algorithm for parallel lines we can construct a parallelogram: Draw a straight line m. Take two points A and B on the line some distance apart. Draw a line n through B at any angle to m. Take a point C on n...
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    High School Can I Find the Logarithmic Expansions of Log[x]?

    The series expansion of any function can be obtained by Taylor's series expansion: f(x)=f(a)+(x-a)f'(a)+(x-a)^2f"(a)/2!+(x-a)^3f"'(a)/3!+... Using the above formula, any function can be expanded in terms of powers of (x-a), provided that all derivatives of f(x) are defined at x=a. Note...
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    Undergrad Is it useful to use patient data for mathematical formulation of tumor growth?

    If Purgum meant that rate is m-n, the differential eqn would be P'(t)=m-n. However, I think, the data given is incomplete. The rate should be dependent in some way on the number of tumour cells; for example, the growth rate proportional to the no of tumour cells and death rate constant. The...
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    Graduate Cross Product: What is the Proof for Its Components?

    What do you mean by component form converts it into three vectors? You want me to show the proof then here it is : We have 3 vectors A(ax,ay,az), B(bx,by,bz) and C(cx,cy,cz) Now A.(B+C)=(ax,ay,az).(bx+cx,by+cy,bz+cz) =ax(bx+cx)+ay(by+cy)+az(bz+cz)...
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    Graduate Cross Product: What is the Proof for Its Components?

    When you define dot product of two vectors (ax,ay,az) and (bx,by,bz) to be axbx+ayby+azbz, distributivity is implied in the definition itself, because it converts dot product into scalar multiplication of components which is obviously distributive. From this definition, one can easily prove that...
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    Fixing Old Dishwasher Motor - Starting Capacitors Needed?

    May be some lubrication can work...
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    Designing a Circuit to Prevent Damage from Higher Voltage Battery: Help Needed

    The calculations are just fine. However, the problem I think is that the 9 V battery may not be able to supply 2.56 A. Why can't you use just two 1.5 V AAA batteries? You may use the batteries in parallel, if required.
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    Difference between AC and DC current

    I would like to clear the concept here. Electron flow and current is not exactly the same thing. In every metal, the free electrons are in continuous motion irrespective of whether a potential is applied across it or not. But this motion being highly random, if we consider any cross section of...
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    Undergrad Using Magnetic Energy: Free Rotation for Life

    Ideally in the absence of non-conservative forces like air resistance, friction, eddy currents, it is possible to bring a magnet into infinite rotational motion regardless of whether it has initial thrust or not.
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    High School How is the dx quantity derived in using differentials to approximate values?

    Though similar, they are not exactly the same thing. In terms of differentials df=f'(x)dx is true but taking dx= -0.6 is only an approximation. In the true sense a differential can be considered as an infinitesimally small change in the variable. You might be knowing the Taylor's series...
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    Undergrad The final explanation to why kinetic energy is proportional to velocity squared

    You agree that work is Fd, right? Now you know that the same force is required for accelerating from 0 to v and from v to 2v in the same time. But if you consider the distance traveled in a given time, it will be definitely more in the velocity range v to 2v than in 0 to v. So more work is to...
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    Graduate How Can We Make 100! Divisible by 12^{49}?

    I think this recursion might be correct, not sure though: 1+1+2+4+7+11+...+(1+n(n-1)/2) = (n+1)(n^2-n+6)/6