Recent content by teken894

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    Emptying a Bowl: Calculating Work

    Homework Statement A hemispherical bowl with radius 8-inches is filled with punch (weighing .04 pound/in^3) to within 2-inches of the top. How much work is done emptying the bowl if the contents are pumped just high enough to get over the rim? Homework Equations The Attempt at a...
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    Shell's Method: Solids of Rotation, Torus

    Homework Statement Volume of Torus: using Shell's mehod 4\pi \int^{1}_{-1}((R-x) \sqrt{r^2 - x^2})dx Homework Equations The Attempt at a Solution I don't know how to integrate this at all. I cannot use any conventional methods...or I can't think of a way... i.e. use isolate a function as...
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    How Do You Calculate Width in a Changing Rectangle with Constant Area?

    use the two equations solve the original area equation and differential equation simultaneously That is, A = wl 0 = 4w - .5l solve the above for w.
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    What are the equations of the tangent lines to both functions?

    Here's a question from my Calc HW andI believe my approach is flawed... Two functions f(x) = x^2 g(x) = -x^2 + 6x -5 Find the two lines tangent to both functions I thought I could find the slope where f' and g' are equal so I did: f'(x) = 2x g'(x) = -2x + 6 2x = -2x +6...
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    How Do You Find a Tangent Line to f(x) = x^2 + 4 That Passes Through (0,0)?

    I know that. You seee (0,0) is not a point on the graph. (0,0) is a given point (outside the graph) which I need to find a line tangent to the graph with. http://66.93.135.68/tmp_pic.jpg
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    How Do You Find a Tangent Line to f(x) = x^2 + 4 That Passes Through (0,0)?

    Seems like a simple problem, but I have no idea how to accomplish this! f(x) = x^2 +4 I have to find a tangent line to the graph that passes through the point (0,0). I know the derivative is 2x, but I don't know how to mathematically figure out the which (x,f(x)) the tangent line would pass...
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    Electric Field Conseptual Question

    Definition It's simple, the electric field is in the direction of force experienced by a small positive test charge. Hence, if protons repel positive charges (force away from the nucleus), so it points away. Convention and definition is the reason.
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    Find Vector Magnitude 27: Algebraic Vectors

    (a • a) would result in a scalar value hence that scalar result would then have to be multiplied with the vector b (scalar multiplication) The final answer is a vector
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    How Do You Calculate the Time a Ball Stays Above a Certain Height?

    y = y_{0} + v_{y0}t + \frac{1}{2}at^2 is the general kinematic equation you want to use, where in your case: solve the resulting quadratic equation for t
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    Michelson-Morley's Experiment: Examining the Ratio T1/T2

    Got that from http://scienceworld.wolfram.com/physics/Michelson-MorleyExperiment.html Good point...I think it's B too since the concept of ether was eventually rejected and the speed of light is found to be constant regardless.
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    How does the force on a bar magnet change as it moves through a loop?

    I know this forumla: \xi = -N \frac {\Delta \phi}{\Delta t} ^^ Faraday's law. It accounts for the number of loops..but for accounting the area of the loop, the flux. phi, depends on area: \phi_{B} = B_{\bot}A = BAcos \theta where A is the area of the coil face. Hence as the...
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    Plotting Graphs: Tips & Shortcuts

    GraphCalc is user-friendly and operated similar to a calculator http://www.graphcalc.com/
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    Solve Long John Silver's Pirate Treasure Puzzle: Find Coordinates

    The keyword here is "half the distance from A to B" You are dividing the coordinate of point B by two, then adding to A..which is wrong. You first need to find the distance, or the VECTOR AB broken down into components: Bx - Ax = ABx By - Ay = ABy which is simply: 60-30 = 30 =...
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    Solving Kirchhoff's Rules: Electric Circuits and Algebra Practice

    This is a problem from my physics book. We are learning Kirchhoff's rules with electric circuits and I'm at a loss at what to do here. I apply them just fine to a three loop circuit, using some algebra: |-/\/\-|\//\ -| | | |--|\--/\/\/--| | |...
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    Help finding coefficient of kinetic friction

    in a ramp, if there was no friction, then the accelration would be 9.8m/s^2? i would guess then..with friction \mu_{k} = \frac{F_{fr}}{F_n} \\ = \ \frac{(mg-ma}{mg-\sin(\theta)mg} is the above correct? I am a HS student too.. or...wait..i messed up the normal force...
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