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  1. P

    Transcription in DNA

    The way I learned it in my Biology course was by referring to the strands as complementary and template strands. The template strand is the non-coding strand - template is a more intuitive way of thinking of it (for me, anyway). The complementary strand has a base sequence that is complementary...
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    Why catalysts affect forward and reverse reactions?

    Ok, that makes sense. Thanks for your help.
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    Kinematics problem

    Actually, I would steer away from saying that you are accelerating. It could cause confusion. I believe the best definition for the OP is that the NET acceleration is zero, acceleration is a change in motion, because the forces cancel out, hence dv/dt (change in velocity over change in time) is...
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    Enhancing the Human body

    Sure you could. It would take a lot of work though, and probably more understanding than we currently have of how the human body works on a cellular and molecular level (as far as I'm aware, anyway). You would have to "program" the appropriate cells to actually incorporate larger amounts or iron...
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    Kinematics problem

    The the action reaction pair is gravity acting on m1 by m2, and the gravity acting on m2 by m1. A rule (not sure if it's actually a rule) that I have found very useful for Newton's 3rd Law is that the action reaction forces must be of the same type, i.e. gravitational and gravitational. The...
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    Why catalysts affect forward and reverse reactions?

    Thanks Vagn and Borek for your prompt replies. I guess I am just incorrectly visualising the "shape" of the active site, and how it bonds with the substrate, whether that be the reactants or products of a particular reaction. It seems strange that an enzyme could not be manufactured to have a...
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    Secondary cell

    In my Year 12 Chemistry course, we learnt that primary cells differ from secondary cells, in that in primary cells, the products of the discharging reaction are used up in side reactions. This is to shift the equilibrium constant to favour the discharging reaction, so the battery will last...
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    Why catalysts affect forward and reverse reactions?

    Based on the very basic understanding on enzymes I have gained from Year 12 Biology and Chemistry, I don't undesrtand why the enzymes specific shape also helps the reverse reaction. I guess my trouble would be due to the simplified diagrams I've seen from Biology, where only the forward reaction...
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    Transformer for a power supply

    Even if it is only to demonstrate the principle practically, I still believe it to be worth a few minutes. I will use many of turns if it increases the efficiency. I assumed that it would, but wanted to be sure. For most purposes, I wouldn't overly care about having fairly precise voltage...
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    Transformer for a power supply

    Thanks for your words of caution, and I'm aware of the dangers of electricity - not first hand experience, just research. I'll definitely use the "Single Hand Technique", especially when experimenting. I just measured the actual voltage from the power point; it's 247V. What would be a good...
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    Transformer for a power supply

    Thanks for the link. That looks quite promising. I may get that, depending on the shipping cost for an overseas 2kVA variac. I would prefer having variable voltages. What I mean by the 5W transformer is just something I can easily build to give whatever voltage I want, and that is safe to use...
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    Transformer for a power supply

    I agree, it probably isn't worth the hassle. I have possibly found the answer. I have found variable transformers online that can deliver even higher powers at lower costs. I am aware that they aren't isolated, and I will research safety precautions in the case that I do purchase one...
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    Transformer for a power supply

    Thanks for the offer, but I'm down towards the bottom of Victoria. I had a look at DigiKey, Element14 and Mouser, but the 300VA 60V transformers all cost >= $100. I could almost buy another Yihua 605d for that much... I have looked up how to build a transformer a bit. I found this site ...
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    Transformer for a power supply

    I am going to make a power supply. I understand the smoothing capacitor and the full-wave bridge rectifier. I am trying to make a 60V, maybe 10A power supply - maybe only 5A, but I would prefer 10A. I don't have a transformer for it, though. I have researched a fair bit on transformers...
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    Multi-layer magnet with seperate coils

    Thankyou for the links. I am using a DC current from a capacitor bank, and I have found a formula for the frequency: f = \frac{1}{2∏\sqrt{LC}} For my coil, it would be something like, C = 0.15F, L = 680μH, which would give a frequency of about 16Hz. Since the frequency is so low, I won't...
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    Calculating actual power (wattage) created by a simple generator

    Sorry, I can't be of anymore help than to correct one of your formulas that you used in your original post: P = V2/R, not P = V/R. So at 4.824V and 1Ω, power would be 4.8242/1 = 23.271W. And you said the induce current would be 4.824W, but it should be in amperes, not watts - just making...
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    Multi-layer magnet with seperate coils

    I am trying to make a very strong magnet that will only last for a short pulse, just a fraction of a second, with a high peak current. I am going to use 1mm (18awg) wire, so the resistance should be pretty low, but with even just 25m, it would be expected to have 0.5Ω. I would like to have...
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    Resistance of a discharging capacitor

    According to this site: http://www.chemi-con.com/components/com_lcatalog/uploaded/8/3/3/48990562506224c250b19.pdf [Broken] at pg26 63V 12000μF capacitors have about 21mΩ ESR. I have 2 of these, so I could connect them in parallel to get a total capacitance of 24mF. Since they are in parallel...
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    Resistance of a discharging capacitor

    I am trying to calculate the maximum current drawn from a capacitor that is connected to a resistor of a very low value (a few mΩ). Because the resistor does not have a large resistance as I've seen with many V/t and I/t graphs for capacitors connected to resistors, where the decay of the curve...
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    Can you help me with measuring electric charge?

    It cannot be measured in force units, because the force on a charge is proportional to the inverse square of the distance between it and another charge. Therefore, the Newton value of it would be from one particular distance. Also, the force is dependant on the Coloumbs of at least 2 charged...
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    Force from power at rest = infinity?

    Ah, so the error was the assumption that just sticking power into something would just magically make it do something. I guess it makes sense, now, as you can't directly propel something with just power, you need the power to be creating a force of some sort. And you would then have force...
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    Force from power at rest = infinity?

    Force can be expressed as F = P/v where P = power (watts) and v = velocity (metres per second) So what happens when you use a given amount of power to accelerate an object from rest? This would be given by: a = P/(mv) And since v = 0 => a = P/(m*0) This would be division by 0...
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    Calculating power in a superconductor

    I may be completely wrong here, but this is what I believe with my very limited knowledge of superconductors, and a little experience with Ohm's Law. A superconductor has zero resistance. Therefore, since V = IR, the voltage drop across the superconductor is given by V = 20000*0 = 0V. So 0...
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    Finding the graph formula with know points and other equation.

    Does anyone have any advice on what I should do to get time into the equation, without velocity on both sides? I don't even know what to type into google to find information on it. Any information would be much appreciated.
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    How can Logarithms be applied to real life situations and examples?

    Logarithms are present in many equations such as the Richter scale for earthquakes, and the Decibal scale for sound power. Also the pH scale for measuring acidity, and the various frequencies of sounds of musical notes. They are just examples of equations involving logarithms, but hopefully it...
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    Finding the graph formula with know points and other equation.

    Oh ok, I'll give it a go: a = (\frac{Pt}{m})ln(|v|)-\frac{C_{D}pAv^{3}t}{6m} Seems to work, thanks.
  27. P

    Finding the graph formula with know points and other equation.

    I have never done differential equations before, and I tried to just find the anti-derivative, but my teacher said that I had done it incorrectly, as I differentiated dv instead of dt, or the other way around. Anyway, here is what I got: v = (Pt/m)*ln(|v|)-(CDpAv3t)/(6m)+c Unfortunately...
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    Finding the graph formula with know points and other equation.

    I have an equation for determining the acceleration of an object being propelled by a constant power source, that is affected by air resistance: a = \frac{P}{mv}-\frac{CDpAv2}{2m} Since F = \frac{P}{v} I am trying to graph this as a velocity-time graph, however, I don't know how to do it...
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    Solving for a variable, transposing equation

    a = (2P / m + u^2)^0.5 - (k*p*A*u^2 / 2m) - u ^ 1 ^ 2 ^ 3 1 - The velocity due to power being supplied, driving it forward, using power to directly change kinetic energy. 3 - Is the velocity before that power was supplied, so velocity -...
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    Solving for a variable, transposing equation

    I went to this website (http://www.1728.org/quartic2.htm) to figure out the quartic equation, I haven't done them before, and I came up with a cubic equation of y^3-3y^2-3y-1=0, which then gave: x1,2 and 3 = 1-1/kp x4 = -3-1/kp But I don't think this is correct somehow, or is not the end...
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