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Primarygun

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Everything posted by Primarygun

  1. I couldn't imagine a strong oxidizing agent other than oxygen can cause fire. Can anyone give an example?
  2. My note said that heat, oxidant and fuel are essential for a fire to occur. Is it possible for a fire to happen without the presence of oxygen?
  3. It's supposed that p.d. of D and E across DCBE is not equal to that across EFD, right? so how can I determine the p.d.?
  4. What will the voltmeter show if it is put at A?
  5. Natural gases contain alkane, such as methane, propane. I've heard that they do not combust with oxygen if oxygen concentration is higher than a certain level. Besides, they do not have smell.
  6. I want to ask something about voltage. Referring to the figure, there's no drop of P.D. across E ,D through EFD. But, through EDCB, there's a P.D difference between them. The voltage across E and D in fact= e.m.f. But why we neglect the first approach? Can anyone reconcile the two approachs.
  7. Is Brutus a strong hacking system? I want to know more of it so as to prevent the attack from it. I have a tremendous curiosity of learning more. hoobie.net/brutus/brutus-aet2.zip {LINK DISABLED DUE TO VIRUS PRESENT} Here's a zip file but my anti-virus software found there's a trojan in it. Please be aware of it.
  8. I am currently studying some simple limit and function. If I didn't browse this web, I didn't know I've entered the Calculus branch. The education system does not fascinate us by the beauty of mathematics.
  9. I think and I hope I know what went wrong. You didn't turn the angle into radian, right? The case is dealing with limit./
  10. Are there any good web sites talking about the possible dangers of domestic electric circuit? For instance, the effect brought about when neutral wire touch the metal cases accidentally. I've been searching the howstuffworks.com for several times, but I could not find what I want. What key words should be typed? I found many irrevelant web sites, some are advertising while some give concise but little information. May anyone help me?
  11. Thank you for replacing with the correct ones. I used a lot of time to doing so but I wasn't able to fix it. For (1), so it would be correct if f(x) is not a fraction? i.e. [Math]f(x)=a_{n}x^n+a_{(n-1)}x^{(n-1)}+....+c=0[/Math] For (2), what about 2=x where c is a real no.? How can we prove that it cannot be further simplified ?
  12. I just started my lesson on my elementary limit recently, and I did many exercises to consolidate my knowledge. I figured out something interesting but I'm not sure whether it is correct. That's why I need your superb help to prove or to reject it. There are several ideas of mine. 1.[Math]\lim_{f(x)\to 0} \frac{1}{f(x)} = 0[/Math] \lim_{f(x)\to\0} \frac{1}{f(x)} = 0 My idea: The limit does not exist. I don't know how to prove it, because if the function is a fraction, I've heard of inverse function. But I have no idea to prove my thought. 2.[Math]\lim_{x\to -2} \frac{1}{[\sqrt(x+2)]} = 0[/Math] The limit does not exist. 3.[Math]\lim_{x\to 1} \sqrt{x-1} = 0[/Math] \lim_{x\to\1} \sqrt{x-1} = 0 My idea: It does not exist because we can't get the limit from the left. Bolded words refer to non-latex .
  13. Can you explain further? I don't know whether the nerve impulse passes through the cerebral cortex to the medulla oblongata.
  14. What about putting 1kg of the gel into water which is poured into a measuring cylinder, then the volume of the gel can be found out. Does this work?
  15. Does the reflex action occurred in eye involve the cerebral cortex of the cerebrum? There are many reflex actions, such as dilation and constriction of pupil...
  16. The numerical one is correct but I'm not sure about the unit.
  17. 1.Can potassium permanganate be used as a bleach? It donates oxygen atoms to the dye. 2.What's the reaction between con. sulphuric acid and ethanedioic acid (COOH)2? Dehydration or CO2 will be given out? When will con. sulphuric acid take out the elements of water of a compound?
  18. I hope this will help you. http://www.scienceforums.net/forums/showthread.php?t=14437
  19. At 100 degree Celsius, energy supplied by heater is used for breaking the bonds(incresing potential energy) instead of giving velocity of molecules(KE)
  20. With you guys' helps, including richard's, I was able to find it out. I could find out 3 methods of getting the answer. Namely, Delta one, Equation one, splitting one.
  21. Oh, answer is E. I understand the word told by my friends wrongly. They said," the initial rate only depends on the Surface A and temperature Difference" I misunderstood it.
  22. Sorry, I mean if a current pass through 1 and, will it be possible for it to pass through this node in opposite direction? For a help please, Iab=Ibe=Iad=Iae?
  23. But the rate of energy loss for them may not be necessarily the same, or the information in the graph is enough to compare their comparison?
  24. Heard that Voltage affect the rate only but not the kind. I found one SP list is telling Ni is above H2. And, I found my book saying that it is reduced during electroplating.
  25. Many friends in this forum told me that the rate of transfer of heat mainly depends on the difference in temperature rather than difference in specific heat capacity. here's an example, what's the answer from you?
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