Recent content by blindside

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    Optimizing Water Flow: Finding Maximum Mass and Rate of Change

    The 3.35 is from the original expression for m, unless you've mistyped it. I used logarithms and the change of base rule to solve for t.
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    What Is the Difference Between Average Speed and Average Velocity?

    At the end of the eight laps the person is where they started, so the final displacement is 0. Since velocity is defined as displacement divided by time, time is irrelevant, and the average velocity is 0 also. You're correct, you've calculated the average speed.
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    Optimizing Water Flow: Finding Maximum Mass and Rate of Change

    a) is, as you said, the solution for t when \frac{dm}{dt}=0. However, the solution to t^{0.2}=\left[\frac{4.8}{3.35}\right] is not 2.3375, check your algebra. b), as you said is m(t) for the solution above c) and d) can both be found by substituting the times into the expression for...
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    Discover the Astonishing Answer: How Many Earths Can Fit Inside the Sun?

    The density of the most efficient sphere packing is \frac{\pi}{\sqrt{12}} \approx 0.9069
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    Centripetal Acceleration of washer spin cycle

    Try an algebraic approach if you can't get it by thinking about it. 3a = 3\left[\frac{4\pi^2R}{T^2}\right] Now get rid of the 3 on the RHS by determining a coefficient for T within the square.
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    How to Calculate Electric Flux for a Rotated Square in a Uniform Electric Field?

    For part b), you can probably see there's a relationship involving the angle. As the square is rotated throughout 90 degrees, the flux that passes through the square gradually decreases to 0. Thus, the trigonometric function you're looking for is cos: 63\cos{40} = 48 For c), the only...
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    Electricity help, calculating the current

    On this site it seems people prefer to encourage independent thought rather than just give the solution, but I'm not sure there's much else to say here. The relations relevant at this level are: V = IR P = IV
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    What is the final speed of the ball when the goalie catches it?

    You need to find the time at which the ball reaches the position of the net. What you've written as g_x is actually just acceleration in the x-direction, g is simply used to denote gravitational acceleration (which only occurs in what's defined as the y-direction in this problem). If air...
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    Radioactive Emissions Basics - Check Answers & Clear Signs

    Uh... not off the top of my head. Gamma is electromagnetic radiation, and is therefore massless and chargeless. Neutrons are almost equivalent in mass to protons (with negligible difference), and therefore have mass 1, and (as the name suggests) electrically neutral, thus no charge.
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    Projectile Motion on an Incline

    I just reworked the problem using the plane of the incline as the x-axis and managed to find for x: x = \frac{2v_{0}^2\cos^2{\phi}\left[\tan{\theta}+\tan{\phi}\right]}{g} Which I assume is what Mindscrape found... Which makes: d =...
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    Current in a solution of NaCl ions.

    They're Na+ and Cl- ions, deficient and in excess respectively of one electron. e = 1.602 176 487 \cdot 10^{-19}C
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    Radioactive Emissions Basics - Check Answers & Clear Signs

    As far as I'm aware, you're correct, the book is not.
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    Projectile Motion on an Incline

    I can't follow that at all.. Firstly shouldn't it be: \cos{\theta}=\frac{AB}{AC} The next equation is just the calculus-derived expression for x, but I don't see how you're getting to the next equation, nor how you're "simplifying" to get the proceeding one..
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    Projectile Motion on an Incline

    Yeah, the solution is quoted in the back of the book, pt a) is correct. The solution to pt b) is \frac{\pi}{4}-\frac{\theta}{2}. I'd like to know how it was solved though. Since the expression for d I found is the solution quoted for pt a) by the text, it seems logical to assume that the...
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