Recent content by PhyStan7

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    Finding the centroid of a cardiod curve.

    For greater clarity I have attached the question ( part b i), I have already done a) and my attempt at a solution. I just think perhaps I am setting up the integral wrong, any hints to get me on the right track would be appreciated, thanks!
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    Finding the centroid of a cardiod curve.

    Homework Statement A cardioid or heart shaped curve is given in plane polar coordinates \rho,\phi by the parametrisation \rho=1-cos\phi or equivilantly \rho=2sin^{2} (\frac{ϕ}{2}) for 0\leq\phi\leq2\pi A shape resembling an apple is generated by revolving the upper (+y) half of the cardioid...
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    Finding basis for kernal of linear map

    Homework Statement Let A = 1 3 2 2 1 1 0 -2 0 1 1 2 Viewing A as a linear map from M_(4x1) to M_(3x1) find a basis for the kernal of A and verify directly that these basis vectors are indeed linearly independant. The Attempt at a...
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    Moment of inertia calculation, factor of radius out?

    Ah i think i understand. So the a in the Ia part of the equation refers to angular acceleration but what i had was the linar acceleration (the situation is one weight hanging off a table and the other being pulled along the table, both are moving with acceleration 3.75). I still do not really...
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    Moment of inertia calculation, factor of radius out?

    Homework Statement Ok i have the following problem. There is a pulley with radius 7.5 cm and 2 forces acting on it (2 tensions of a string) acting in opposite directions either side. One is 18.2N, the other 7.5N. I know the acceleration is 3.75 meteres per second squared. Find the moment...
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    Double integration - finding the limits

    Hello, I am stuck on this double integration question as I am not sure how to get the limits to integrate between. If anyone could give me advice on ways to get limits in general, help would be appreciated.Homework Statement Evaluate the following integral R(xy+cosx)dxdy where R, the region...
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    Simple complex number question

    Cheers tiny-tim! So is this right... 343e(2i)ln7=reiθ and as reiθ=r(cos(θ)+isin(θ)) θ=ln49 and r=343? Or have i gone wrong somewhere? Cheers
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    Simple complex number question

    Sorry i can tell I am being stupid and missing something here. Homework Statement if 7^(3+2i)=re^(i[theta]) find values of the real numbers r and [theta] Homework Equations er^(i[theta])=r(cos[theta]+isin[theta]) The Attempt at a Solution Ok you know that...
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    Finnding the error in approximating an infinite series

    Hi, sorry i wasnt quite sure where to post this. I think i know how to do it but have not encountered a question like it and don't have a mark scheme so thought id post it up to see if my thinking is correct. Homework Statement (c) By considering the integral of 1/(x^3) between N and...
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    Integration Problem: Solving 3/(1+4x)^0.5 from x=0 to x=2

    Hi all, I am having a problem with an integration. Solve the integration 3/(1+4x)^0.5 between x=0 and x=2. Basically find the area under a curve of the equation between x=0 and x=2. I know the answer is 3 but can't get to it. I tried rewriting it as 3(1+4x)^-0.5 and solving bu got stupid...
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    Distance it takes for terminal velocity

    Hi, i just wondered if it is possible by calculation to determine how far in a viscous liquid it would take for an object (sphere, ball bearing) to reach terminal velocity. I have to design an experiment to investigate Stokes law. Could i use suvat equations as it is constant acceleration? Thanks
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    Subtracting integers with powers

    Homework Statement Hey, sorry about this. Its really obvious, i think there's just some really simple way to do it. Its annoying me, my teacher couldn't do it either! Evaluate 6667²-3333² (without a calculator) Homework Equations The Attempt at a Solution I know there is just...
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    How Does Rocket Mass Loss Affect Exhaust Gas Velocity for Lift-off?

    Yeh I am not sure about the time. I didnt think it was t=0 as i thought no gas would have been released. But I am sure which ever it is as long as I've done the right method my teacher won't mind. Thanks for the help guys!
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