Recent content by sluo

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    Calculating total energy carried by a ripple

    THanks guys! By the way, do you guys have any idea about how to derive the formula for the potential energy in the case of the 1D string? (It comes out the same as the KE, but I can't figure out why)
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    Calculating total energy carried by a ripple

    Ok, so since the motion is described by something like A\sin(\phi) the velocity for one radial section is something like A\cos(\phi) , and so the kinetic energy is proportional to A^2 . So by conservation of energy, the energy is always prportional to A^2 . Next, since the ripple grows...
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    Calculating total energy carried by a ripple

    I kind of see what you're saying, but i don't see how the radius comes into it. In the 1D case, it didn't depend on the distance from the source.
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    Calculating total energy carried by a ripple

    Homework Statement A two-dimensional water wave spreads in circular ripples. Show that the amplitude A at a distance R from the initial disturbance is proportional to 1/\sqrt{R} Hint: Consider the energy carried by one outward moving ripple Homework Equations Kinetic energy carried by...
  5. S

    Diameter of a stream of water from a faucet

    Thank you, yes I was forgetting to square the A_1. And the answer is .247cm, not 2.47cm. I kept everything in cm throughout. Thank you!
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    Diameter of a stream of water from a faucet

    Here is my work: A_1v_1 = 125 cm^3/ 16.3 s \\ v_1 = 125/(16.3 *\pi*0.48^2) = 10.6 cm/s Next, write v_2 = A_1v_1/A_2 and plug into Bernoulli's equation. If we take P_1 = P_2 , then the density cancels out and it simplifies to 2gh = v_2^2 - v_1^2 = \Bigg(\frac{A_1^2}{A_2^2} - 1\Bigg)v_1^2...
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    Diameter of a stream of water from a faucet

    The book lists the correct answer as 0.247 cm. I keep getting 0.268 cm. It seems from your equation above, that you took P_1 = P_2 even though you said that there should be some difference. So is there a pressure difference or not?
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    Diameter of a stream of water from a faucet

    Homework Statement Consider a stream of water flowing from a kitchen faucet. At the mouth of the faucet, the diameter of the stream is 0.960 cm. The stream fills a 125 cm^3 container in 16.3 seconds. Find the diameter of the stream 13.0 cm below the mouth of the faucet. Homework...
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    Pressure measurement in U tube with mercury and water

    I didn't think of that... but I'm wondering how it helps because we don't know the height of the U tube or the original height of the mercury in each arm.
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    Pressure measurement in U tube with mercury and water

    Homework Statement Mercury is poured into a U tube. The left arm of the tube has a cross sectional area A_1 of 10 cm^2 and the right arm has a cross sectional area A_2 of 5 cm^2. One hundred grams of water are then poured into the right arm of the tube. A: Determine the length of the...
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    How pressure is measured using a manometer

    Hello. I'm reading a physics book on my own and am learning about pressure measurements. I have a question with how pressure is measured using a manometer. Here is a link talking about it: http://www.upscale.utoronto.ca/PVB/Harrison/Manometer/Manometer.html My question is, why do points...
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