Recent content by mike_302

  1. M

    How much power is the customer receiving?

    Homework Statement 8. An electric utility company supplies a customer's house from the main power lines (115 V) with two copper wires, each of which is 53.6 m long and has a resistance of 0.125 Ω per 294 m. Calculate the voltage at the customer's house for a load current of 110 A...
  2. M

    Horizontal Velocity Question: Which Object Falls First at 12m/s and 16m/s?

    Well, the object is always experiencing one acceleration in this case: gravity, and we all know that is 9.81 m/s^2 down. So which of the balls will reach 0 m/s first, if one starts at 12 and the other 16? Neither one has an advantage in the rate at which they go to 0 m/s... They both move...
  3. M

    What is the maximum power required for an ore car to accelerate up a mine shaft?

    Okayyyy. So either one of those equations works just as well for non accelerating systems, but the one with speed will find my maximum work given a specific speed. I understand. Thanks guys! That actually helped a tonne!
  4. M

    What is the maximum power required for an ore car to accelerate up a mine shaft?

    Sorry... I think I need that explained a little differently. Which scenario is it better to use which of those equations for? I mean, I understand the derivation of those equations, but why use F*v rather than W/t in any given situation?
  5. M

    What is the maximum power required for an ore car to accelerate up a mine shaft?

    OHhhhhhh okay. We didn't cover that in our lectures so I have a feeling this question was just out there... to make us think. It's good though. So let me get this straight: Power=Work/Time (constant power) Power=F*v (changing power)
  6. M

    What is the maximum power required for an ore car to accelerate up a mine shaft?

    Homework Statement A loaded ore car has a mass of 950 kg and rolls on rails with negligible friction. It starts from rest and is pulled up a mine shaft by a cable connected to a winch. The shaft is inclined at 30 degrees above the horiz. The car accelerates uniformly to a speed of 2.2 m/s in...
  7. M

    How Does Conservation of Energy Apply to Motion Down a Hill?

    Homework Statement My attempt at a solution was to say: Eki = Ekf + Eg and my Ek 's all has 1/2 on them... other than that, my solution is essentially the same thing. I end up with sqrt( vi2 - sg(delta)h ) = vf What's up with this?
  8. M

    Notation within homework question

    Okay, I completely see why it's Ui-Uf now but that U(x,y) notation seems messed up because there's no typo :P That's how it is written, and I get the answer using JUST x, so I guess it should've said U(x)= ... Oh well!
  9. M

    Notation within homework question

    Homework Statement A particle moving along the x-axis is subject to a conservative force such that the potential energy of the particle is given by U(x,y)=2x + x^3 where x and y are in meters, U is in joules. When the particle moves from (2,0) to the origin, the work done by the...
  10. M

    Electric Field at Point Z, Two Charges

    Figured it out... I dropped the sin(53.13) when I multiplied by 2... but to answer your question, sin(180-theta)=sin(theta)
  11. M

    Electric Field at Point Z, Two Charges

    woah... woah... why? tan(theta)=.04/.03 ... that's unarguable... that gives my radius... And in the Y-component part, we are taught to use sin(theta) for Y-components, where theta is the angle from the positive x-axis.
  12. M

    Electric Field at Point Z, Two Charges

    Homework Statement I have drawn the diagram on the attached page... IT contains all information. The question is simply to determine the electric field force at point Z (which is at the very upper edge of the page) Homework Equations epsilon= Fe/q The Attempt at a Solution...
  13. M

    How Does Physics Explain Unbreakable Egg Holders and Rotating Drop Models?

    Here's one I reallly need help with guys. Lets say I wanted to make a model that rotated like a maple key... You know what I mean? A blade or two that turned all that gravitational into kinetic. How would I go about building this model in under 75 grams? I'll bet I can brainstorm materials if I...
  14. M

    How Does Physics Explain Unbreakable Egg Holders and Rotating Drop Models?

    the fan idea has been intriguing me for a while, and I've kept it in mind, but I made a brand new design that has, so far, been kicking butt. I will need to lose some weight on it after I determine whether it is the godsend I think it is, but as of right now, I have a sturdy laminate gift box...
  15. M

    How Does Physics Explain Unbreakable Egg Holders and Rotating Drop Models?

    Thanks. I'll try that. So it's about center of gravity I am guessing. Will still need a new box, but I'll try and get that this weekend and run a few trials.
Back
Top