Recent content by quanticism

  1. Q

    Cathodes/Anodes in Chemistry and Physics

    Thank you very much! I finally see the light now :)
  2. Q

    E-field greater at sharp edges?

    The charge density is indeed higher at sharper regions. I think this site is quite good at explaining why. http://www.physicsclassroom.com/class/estatics/u8l4d.cfm Just scroll down to the "Electric Fields and Surface Curvature" section and it'll explain how the sharper regions results in a...
  3. Q

    Cathodes/Anodes in Chemistry and Physics

    Hi, I'm confused at why cathodes are the positive terminal in chemistry but appear to be the negative terminal in physics. I hope someone can clear this up for me. Definitions: Anode: An anode is an electrode through which conventional current flows into a polarized electrical device...
  4. Q

    High voltage distribution to reduce power loss

    Thanks for the reply. Let me just check my understanding So U^2 Rw/(kR)^2 shows that as k increases, the power wasted decreases. V = U(k + Rw/(kR)) shows that as k increases from 0, V will first decrease to a stationary point and then increase. The k used in practice is large so it's past the...
  5. Q

    High voltage distribution to reduce power loss

    You lost me at this step. Wasn't the constraint to keep the power delivered by source constant? So I would agree with this bit: "the voltage now being ℜV and the current I/ℜ" But saying: "If the load is a resistance R_load, it now becomes ℜ2R_load to account for the same power" means you're...
  6. Q

    High voltage distribution to reduce power loss

    "But first you have to agree on what you regard as a given." What do you mean by this? By given, do you mean a fixed value has been assigned to it? If yes, then the paragraph below has relevance. If not, then I'm not sure what's happening anymore. So in the first set, are you implying that...
  7. Q

    High voltage distribution to reduce power loss

    Did you look at the image I linked in the OP? I wrote: Vwire = Vsupply (Rwire/(Rwire + Rload) ) implying that the voltage drop across the wire was directly proportional to the total voltage supply
  8. Q

    High voltage distribution to reduce power loss

    I was wondering if there was a better model where the all the simple ohmic equations and power equations will be entirely consistent and not just close. lol, I subscripted V_supply and V_wire to highlight that I was aware of the difference between the two. Though it's understandable that you...
  9. Q

    High voltage distribution to reduce power loss

    So since no one else commented, does everyone agree with voko's explanation? From what I understand, voko is saying: 1) Take consumer voltage as a constant value with their load R 2) High voltage distribution side of it will see the consumer load as Rk^2 3) If k increases, Rk^2 increases so...
  10. Q

    High voltage distribution to reduce power loss

    So you're saying that the value of the load impedance is wrong because I didn't perform a impedance transformation from the secondary (low voltage) coil to the primary? R_load in the diagram is an arbitrary number so it doesn't matter if it's been scaled by the constant k^2 right? (k = turns in...
  11. Q

    High voltage distribution to reduce power loss

    Homework Statement In Australia, New South Wale's final year of high school, a common question is asking something like: How does distributing electricity at high voltages reduce power loss in the transmission lines.Homework Equations P = VI = (I^2)R = (V^2)/R. Not very clear without...
  12. Q

    Finite Well Potential - Unbound eigenfunction

    Homework Statement From qualitative arguments, make a sketch of the form of a typical unbound standing wave eigenfunction for a finite square well potential. An unbound particle is one which has total energy E greater than the Potential V of the well Is the amplitude of the oscillation the...
  13. Q

    Easy Limits Q. Homework: Show $\lim_{x\to2}\frac{x+1}{x+2}=\frac{3}{4}$

    Ah sorry, you are correct. Guess I was so focused on the x's and epsilons that I forgot about the constant.
  14. Q

    Easy Limits Q. Homework: Show $\lim_{x\to2}\frac{x+1}{x+2}=\frac{3}{4}$

    Shouldn't it be |x-2|<e|x+2| ? But apart from that I think I see where you're going. If |x-2|<1, then |x+2|<5. So we have |x-2|<5e<e|x+2| ...(1) So we pick a \delta to be 5e such that 0<\delta<1 which would work if epsilon was small. Edit: Opps, (1) should be |x-2|<e|x+2|<5e which isn't...
  15. Q

    Easy Limits Q. Homework: Show $\lim_{x\to2}\frac{x+1}{x+2}=\frac{3}{4}$

    I'll show what I did and you can point out any errors/invalid algebraic manipulations. |\frac{x-2}{x+2}|<\epsilon ...(1) |\frac{x-2}{x-2+4}| < \epsilon |\frac{1}{1+\frac{4}{x-2}} <\epsilon Now note that by applying triangle inequality: \frac{1}{1+|\frac{4}{x-2}|}} \le...
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