Recent content by student_fun

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    Solving the Resistance of an Electric Water Heater

    Gotcha. Thanks for the hint. Looks like Q = mc delta T works great for calculating necessary heat to heat the water while v squared over R multiplied by time (in seconds) equals the heat generated by potential and resistance over time. I appreciate your time in providing the hint.
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    Fabricate uniform wire out of 2.1g of copper w/ 0.3 ohm resist. - wire diameter?

    ah geeze, thanks for pointing that out. The proper density I should have used was 8940 kg / m3. That solved it. Thanks for pointing out my simple error :) Was up till 2 AM which explains the silly error.
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    Solving the Resistance of an Electric Water Heater

    Homework Statement A well-insulated electric water heater warms 137 kg of water from 20°C to 45.0°C in 16.0 min. Find the resistance of its heating element, which is connected across 220-V potential difference. Homework Equations R=V/I The Attempt at a Solution Not sure how to...
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    Fabricate uniform wire out of 2.1g of copper w/ 0.3 ohm resist. - wire diameter?

    Homework Statement Suppose you wish to fabricate a uniform wire out of 2.1 grams of copper. If the wire is to have a resistance of 0.3 ohms and if all of the copper is to be used, what must the diameter of this wire (in mm) be? Homework Equations mass (in kg), cross-sectional area...
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    0.5V across 1.5m tungsten wire w/cross-sect. area 0.6 mm^2 - Find wire current

    Thanks for the reply fball558 :) It's nice to get other views while your pourin over pages and pages of physics :)
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    0.5V across 1.5m tungsten wire w/cross-sect. area 0.6 mm^2 - Find wire current

    Nevermind, lol, solved my own problem. Found out that I didn't convert millimeters squared to meters squared. Got it right now :)
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    0.5V across 1.5m tungsten wire w/cross-sect. area 0.6 mm^2 - Find wire current

    Homework Statement 0.5 volts is maintained across a 1.5 meter tungsten wire that has a cross-sectional area of 0.6 mm2. What is the current in the wire? Homework Equations Resistivity of tungsten: 5.6E-8 ohm meters. Current Density: J = \sigma \cdot \frac{V}{l}, J = \frac{I}{A}...
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    Help with an angled atwood machine problem

    Hey Guys, I have attached my problem and all my work for it. The work presented in my handwriting is the attempt I figure most accurate. All my other attempts were experimental to no avail :( I think I must be overlooking something really basic. Any assistance or pointers are greatly...
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