Recent content by clementc

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    Solve Volume of Revolution Problem: y=x^{-2} to y=e Rotating Around Y-Axis

    Sorry for lag reply. Oh my god I've just spent the last 30 min scribbling furiously away at my desk because I was getting different answers from 2 different methods and didn't know why. When I did your way I got it wrong because the algebra was more complicated. So YEAH I really recommend just...
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    Solve Volume of Revolution Problem: y=x^{-2} to y=e Rotating Around Y-Axis

    Can I assume that the question means the area above the x axis? Anyway, firstly you must draw the graph. Are you trying to find the volume of the cylinder then subtract the volume not included in the region? If so isn't the x=1 the outer radius? And so then rather the inner radius should then...
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    Exam question, simple physics calculus.

    Haha, all righty, first of all 595 - 325 = 270! http://img26.imageshack.us/img26/2167/screenshotdocument1micr.png I sometimes find drawing a picture simplifies things. The first picture on the left shows the amount of water (LIGHT BLUE WATER) that will be displaced AFTER the screw is dropped...
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    Kicked ball hits bird and falls

    No need to make it so complicated; most projectile questions can simply be solved using the 3 equations. v = u + at s = ut + 1/2 at^2 v^2 = u^2 + 2as All you need is to think about the initial condition, and final condition. - To find the velocity at the very peak (i.e. right before impact)...
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    What is Heisenberg's Uncertainty Principle?

    What is Heisenberg's Uncertainty Principle?? Homework Statement Hey everyone, Until very recently, I had always thought that Heisenberg's uncertainty principle was that \Delta x \Delta p \geq \frac{h}{2\pi} (or \hbar) However, I'm doing my final year of high school physics this year...
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    Electric potential of a spinning rod.

    I think you're thinking of the potential of a single point charge - I think the formula for the potential of a dipole in an electric field given by U = -\mathbf{p} \cdot \mathbf{E}
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    How to find a radius of a circular ring from a given equation

    Wouldn't the gradient of the line, m, just represent EA? And you know E already!
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    Masses on a rod inertia problem

    Without calculus =( Well, in a dodgy series notation kind of thing... I=\sum mr^2=m_1 r_1^2 + m_2 r_2^2 + m_3 r_3^2 +... In other words, the moment of inertia of a body is just the sum of all the individual moment of inertias of every point on it. For example , if I had a rod of negligible...
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    Calculate the energy associated with the magnetic field of a solenoid

    I'm not 100% sure but I think the formula you're missing here is the one for inductance: L=\frac{N\Phi_B}{i}
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    1D Elastic Collisions with air gliders

    There's a much neater way of doing this! Try using the difference of 2 squares and dividing the KE conservation equation by the momentum conservation equation
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    B-field question Lorentz's force

    It's meant to just be the KE I think - there's no change in KE There's only centripetal force in this problem - the "tangential force" you're talking about doesn't exist =\
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    Calculating Force of Friction: 36N Applied to 6kg Cart with 5.5m/s Acceleration

    Find the net force using F=ma. Try to go from there
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    Another Angular Velocity question

    remember the equations linking the rotational counterparts with their linear equivalents: v=r\omega Every point on the Earth has the same angular velocity \omega, but depending on the radius of the circular path which it traces, its tangential velocity will vary. To have a tangential velocity...
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    Calculating Spring Compression of Ore Car on Downhill Mine Tracks

    Yeah there doesn't seem to be anything wrong with it =\
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