Recent content by vaxopy

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    Generators (know r, l, B, angular speed of coil) how to find peak EMF?

    i had to do a similar question.. cant remember how i did it though >_<
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    How can you get power used from step down transformers

    Suppose there are two transformers between your house and the high-voltage transmission line that distributes the power. In addition, assume that your house is the only one using electric power. At a substation the primary of a step-down transformer (turns ratio=1:29) receives the voltage from...
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    Magnetic Field Inducing Electric Field - Lighting a 60W Bulb

    please help me.. i don't know much calculus P = V^2/R im assuming V = emf in the equation emf = vBL so 60W = emf^2/240ohms emf = 120V.. but they do not give me a velocity or anything im stumped :/
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    Magnetic Field Inducing Electric Field - Lighting a 60W Bulb

    Suppose the light bulb in Figure 22.4b is a 60.0-W bulb with a resistance of 240 W. The magnetic field has a magnitude of 0.40 T, and the length of the rod is 0.60 m. The only resistance in the circuit is that due to the bulb. Minimally, how long would the rails on which the moving rod slides...
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    Need help on torques / magnetic fields

    A square coil and a rectangular coil are each made from the same length of wire. Each contains a single turn. The long sides of the rectangle are twice as long as the short sides. Find the ratio tsquare/trectangle of the maximum torques that these coils experience in the same magnetic field when...
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    Is This Calculation of Magnetic Field at the Center of a Solenoid Correct?

    B = uNI/2L * (L/2/(\sqrt{((L/2)^2)+R^2)} - (-L/2/(\sqrt{((-L/2))^2+R^2))} I get.. B = uNI/2R (for those wondering, this is the equation to find the magnetic field when a Hall probe is placed in the center of a solenoid) they ask me to figure out the % diffeerence between the field at the...
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    Please help me with resistors in parallel/series - with many variables

    Please help me with resistors in parallel/series - with many variables :) Three identical resistors are connected in parallel. The equivalent resistance increases by 700 W when one resistor is removed and connected in series with the remaining two, which are still in parallel. Find the...
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    Aluminum wire, current, voltage, density, find mass

    An aluminum wire is hung between two towers and has a length of 175 m. A current of 125 A exists in the wire, and the potential difference between the ends of the wire is 0.300 V. The density of aluminum is 2700 kg/m3. Find the mass of the wire I have no idea how to do this :'(
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    Electric potential energy - how is it conserved?

    im so confused :'( is what I am doing correct?
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    Charged particle thrown upward (almsot there)

    The electric potential at the height h exceeds the electric potential at ground level potential at top > potential at bottom, potential at top is more positive then at bottom I figured out h with Vf^2 = Vi^2 + 2ah 30^2 = 0 + 2(-9.81)h h =45.87m (changed it) energy required to get it to...
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    Electric potential energy - how is it conserved?

    Electric potential energy - how is it conserved? obviously the answer is yes , its conserved.. but something bugs me about it. One particle has a mass of 3.00×10–3 kg and a charge of +8.00 mC. A second particle has a mass of 6.00×10–3 kg and the same charge. The two particles are initially...
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    Charged particle thrown upward (almsot there)

    A particle is uncharged and is thrown vertically upward from ground level with a speed of 25.0 m/s. As a result, it attains a maximum height h. The particle is then given a positive charge +q and reaches the same maximum height h when thrown vertically upward with a speed of 30.0 m/s. The...
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    A hypothetical pressure question lifting a 10,000kg object

    Lets say you have a very long (and strong) tube (310m high) filled with water. at the bottom, the tube comes back up, forming a U shape. if the radius at the end of this U shape was 0.1m.. does this mean that (absolutely regardless of the radius of the top at the top, and therefore the...
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    A hypothetical pressure question what if u covered the top of a container?

    Lets say u have something like this | | => A |------| => B | | | | | | |------| => C (1m below the metal seperator) B => this is a strong metal seperator.. the water on top of this sits on this. the seperator is attached to the container..it does not float...
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    Very simple question - is pressure 1m down in water.

    the small p is rho and i figured it out :) its the 2nd eqn
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