Recent content by timmastny

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    Electric Potential and bounds of integration

    Homework Statement Find the potential difference between V(P) - V(R) and V(c) - V(a) Homework Equations Electric potential: V(a) - V(b) = \int^{b}_{a}E*dr V(b) - v(a) = -\int^{a}_{b}E*dr Fundamental Theorem of Calculus: F(b) - F(a) = \int^{b}_{a}f(x)dx The Attempt at...
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    Double Integrals in polar coordinates: Calculus 3

    No problem, multitasking makes breathing hard, haha. That makes perfect sense though. That means the upper limit of integration depends on θ. So many problems in polar coordinates have static bounds, I completely forgot about that. Thanks! P.S. I just calculated the new integral, it is...
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    Double Integrals in polar coordinates: Calculus 3

    3pi/4 is 135 degrees. According the limits of integration, x only varies from 0 to \sqrt{6}. \theta cannot go past the limits set by x. If \theta varied from pi/4 to to 3pi/4 wouldn't the limits of x be different? However, I agree it is a triangle but I think the triangle is in positive x...
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    Double Integrals in polar coordinates: Calculus 3

    Homework Statement Given \int^{\sqrt{6}}_{0}\int^{x}_{-x}dydx, convert to ploar coordinates and evaluate. Homework Equations We know that x=rcos\theta and y=rsin\theta and r =x^2+y^2 The Attempt at a Solution First, I defined the region of the original integral: R = 0...
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    Physics Concerning particle physics and job availability

    ParticleGirl, you mention an optics focus would give some one more opportunity to do research? Any reason? In your opinion, is there any other fields that could give a physicist a better opportunity to do research?
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    Can MyFitnessPal and Zumba Help Me Lose Weight?

    Just wanted to stress the importance of what Ben Niehoff said. Starting Strength is one of the best things to happen to me. I'm shocked to hear recommendations for sugary foods like fruits and more carbs instead of a foundation of adequate, complete protein (which is mostly found in meat).
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    Rolling Sphere Oscillating on Spring

    UPDATE: Rereading the section on Rolling without Slipping, I'm not sure I'm supposed to set F_{static}R = I\alpha where I follows the parallel axis theorem. So instead of I = 2/5MR^{2}+MR^{2} I think it should just be equal to I = 2/5MR^{2} That said, I have tried this solution but I was...
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    Rolling Sphere Oscillating on Spring

    UPDATE: I couldn't figure out what was wrong with my previous answer, but I found something I did wrong in my calculators. I was using big M to denote total mass. However in my calculations I was multiplying by .862 Revised with total mass 1.724 and plugging into 2*pi*sqrt(12M/5K) I found T...
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    Rolling Sphere Oscillating on Spring

    Homework Statement Two uniform solid spheres, each with mass 0.862 and radius 8.00×10−2 , are connected by a short, light rod that is along a diameter of each sphere and are at rest on a horizontal tabletop. A spring with force constant 164 has one end attached to the wall and the other end...
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    Why Can People Typically Leg Press More Than They Bench Press?

    Russ's answer pretty much answers your question Munyit. Legs can be weaker than arms. You say, "Actually I mean maybe is it possible for someone's arms become stronger than their legs without their legs being injured or crippled." The answer is yes. One simply trains their upper body and...
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    Why Can People Typically Leg Press More Than They Bench Press?

    FInally, an area I have knowledge. First, SIZE. Starting Strength, 2nd Edition by Mark Rippetoe on page 83 explains the notion of cross-sectional area. He elaborates, "a third class lever exhibits greater efficiency the more closely the force is perpendicular to the resistance, no matter what...
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