Recent content by r_swayze

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    Solve Thin-Film Equations: Red Light on Oil in Water

    Homework Statement White light illuminates an oil film on water. Viewing it directly from above, it looks red. Assume that the reflected red light has a wavelength of 615 nm in air, and that the oil has a thickness of 2.640e-7 m. What is the refractive index of the oil? Assume that the...
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    Inductance Formulas Homework: Find Emf & Time to Drop Below 1.25mV

    Homework Statement The current in a 4.70 mH inductor decays over time according to the following function, where t is in seconds. I(t) = (.943A) e-(396 s-1) t) (a) What is the induced emf across the inductor at t= 5.00 ms? (b) How long does it take the emf to drop below 1.25 mV?The Attempt...
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    Circuits with series and parallel wiring

    Four identical 5.00 Ω resistors are joined and form the four sides of a square. (a) What is the resistance between points A and B? (b) What is the resistance between A and C? The answer to (a) is 3.75 and (b) is 5, but I have no idea how to get those answers. Can somebody help?
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    How Does Kirchhoff's Loop Rule Apply to Multi-Battery, Multi-Loop Circuits?

    (a) What is the magnitude of the current that flows through branch AB? (b) In what direction does the conventional current flow in branch AB? (c) What is the magnitude of the current that flows through branch CD? (d) In what direction does the conventional current flow in branch CD? I don't...
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    Circuits with Series/Parallel Wiring

    but if the 20 resistor were to go out, then wouldn't there still be a path for the 6 resistor to reach the battery? I thought the definition of parallel was a junction between resistors.
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    Circuits with Series/Parallel Wiring

    (a) What will the ammeter read? Report this as a positive number. (b) How much power is dissipated by one of the 10.0 Ω resistors? I am confused about which circuits are in series or parallel wiring. I know the small 10 ohm and 10 ohm loop is parallel, and the 20 ohm to 6 ohm are parallel...
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    Change in Electric Potential Question

    In Ernest Rutherford's scattering experiment, described in detail in an earlier homework problem in this chapter, alpha particles (with a mass of 6.68×10–27 kg and a charge of 3.20×10–19 C) come from a few milligrams of radium (to be very precise, its decay product radon). They leave with an...
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    Potential difference, electric potential energy and work

    Four charges are arranged at the corners of a rectangle as shown in the diagram. How much work needs to be done to move the charge q2 to infinity? Since change in PEe = W, am I suppose to find total potential electric energy of the four charges and then subtract the total potential electric...
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    How Does a Charge Affect a Uniform Electric Field?

    A particle with charge +7.88 μC is placed at the fixed position x = 3.00 m in an electric field of uniform strength 300 N/C, directed in the positive x direction. Find the position on the x-axis where the electric field strength of the resulting configuration is zero. I don't understand...
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    Beat FrequencyWhat is the new tension in the string that slipped?

    Two identical strings are sounding the same fundamental tone of frequency 156 Hz. Each string is under 228 N of tension. The peg holding one string suddenly slips, reducing its tension slightly, and the two tones now create a beat frequency of three beats per second. What is the new tension in...
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    Balancing Equation using redox reactions?

    The problem states: "Balance the following redox reaction: In basic solution, oxygen difluoride reacts to produce fluoride ion, oxygen, and water." I figured out one way of doing it by just adding H2O, H^+ ions, and OH^- ions to either side and balancing it, but I want to know how to do it...
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    Balancing Equation using redox reactions?

    OF2 --> F- + O2 + H2O OF2 --> F- 2H+ +OF2 --> 2F- + H2O 2H+ +OF2 + 4e- --> 2F- + H2O This is as far as I can get. I don't know how to do the other half of the redox since the equation would be: OF2 --> O2 + H2O What do I do here? Maybe I am not setting this up correctly?
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    Resolve Overflow Issue: Log(K) = 127.702 | K = 5.04316 * 10^127

    "If your calculator has overflow issues with this problem, you can use this identity to solve for K: if log(K) = x + y then K = 10x * 10y Problem: log(K) = 127.702 K = 5.04316 * 10127 " Doesn't K = 10127 ? Where are they getting the 5.04316 from? How are they using that specified...
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    Torque and Angular Acceleration

    The pulley shown in the illustration has a radius of 2.70 m and a moment of inertia of 39.0 kg∙m2. The hanging mass is 4.20 kg and it exerts a force tangent to the edge of the pulley. What is the angular acceleration of the pulley? All I have so far is the force exerted on the pulley by the...
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    Calculating Final Speed of Engine-less Space Capsule Launched from Earth

    ok, but then how would I find the radius needed for that orbit? I can't just plug in 0 for F = GMm / r^2, right?
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