Recent content by Avalanche

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    Voltage drop across capacitor in RC circuit

    C = (1/4+1/11)^-1 = 2.9333 Time constant = RC = 5*2.93333 = 14.6667 microseconds 0.5 = e^(-t/14.6667) t = 10.2 microseconds Thanks for all the help! btw ... does it also take 10.2 microseconds for the potential across the 6 microfarad resistor to drop to half of its initial value?
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    Voltage drop across capacitor in RC circuit

    The time constant = RC. The only resistor is the 5 ohm resistor. Is that R? And for C, do I use the equivalent capacitance or just the 4 microfarad?
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    Voltage drop across capacitor in RC circuit

    No ... it's the right loop. When the capacitor discharges, it creates a current that flows around the right loop. I3 becomes zero. Is that correct?
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    Voltage drop across capacitor in RC circuit

    When the circuit is opened, the left loop should still has current because there is a battery in that loop.
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    Voltage drop across capacitor in RC circuit

    Homework Statement Please look at the attachment for the circuit. The question is this: The switch has been closed for a long time. It is then opened. How long does it take for the potential across the 4μF capacitor to fall to half of its initial value? Homework Equations V =...
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    How long it takes to discharge capacitor when switch is opened

    I guess my question was why the equivalent resistance wasn't this
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    How long it takes to discharge capacitor when switch is opened

    I think I kind of get it. Why do you have to rearrange the circuit? Is it because you want the resistors to be in parallel with the capacitor?
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    How long it takes to discharge capacitor when switch is opened

    Homework Statement Please look at the attachment. The part I am having problems with is part C Homework Equations time constant = RC Q = Q0 e^(-t/RC) The Attempt at a Solution I don't understand why the circuit is equivalent to the 4 ohm resister with the 18 ohm resistor in series so that...
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    Ranking springs in terms of spring constant

    Looking at the answer, I assume springs in parallel have greater spring constants, then springs by itself and springs in series have the smallest spring constant. Is there a reason for this? Like an equation/relationship?
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    Ranking springs in terms of spring constant

    Greater the mass, greater the spring constant. Longer the spring stretches, smaller the spring constant. Since C stretches by the largest amount and has a mass of only m, the spring constant is the smallest. A and B stretches by the same amount and have the same mass, the spring constants are...
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    Ranking springs in terms of spring constant

    Homework Statement Homework Equations Hooke's law. F = kΔx ω = sqrt(k/m) The Attempt at a Solution For part A F = mg = kΔx k = mg/Δx g is a constant so the spring constant is proportional to the mass and inversely proportional to the change in distance that the spring...
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    Solving for Density: Buoyant Force & Force of Gravity

    So the mass of the board= density of water*volume of water displaced Because the object is floating, the volume of the water displaced is equal to the volume of the submerged part. so volume of water displaced = vo = 0.12 m^3 = 1000*0.12 =120 kg density of boat = m/v =120/0.36 = 333.3 kg/m^3...
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    Solving for Density: Buoyant Force & Force of Gravity

    I need the mass of the object. How do I find that? Is rhoo equal to the density of water?
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    Solving for Density: Buoyant Force & Force of Gravity

    Homework Statement Homework Equations density = mass/volume FB = rhoo vog for a floating object F = mg The Attempt at a Solution Buoyant force = force of gravity due to the board rhoo vo = m vo = area*height submerged vo = 2.4*.05 vo = 0.12 m^3 volume of the board =...
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    How does the reference height affect Bernoulli's principle calculations?

    So for this question, the reference height of 0 is already set at the manometer? Is it possible to use the reference height at the beer level in the container?
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