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    Assignment from my biology teacher on karyotypes

    Well, you'll be able to state its sex by knowing whether or not your karytope had (X,Y) or (X,X) sex chromosomes. As for the extra large chromosome, it could be that your karyotype shows a mutation, such as a trisomy disorder. Since you said it was an "extra big chromosome," it must be one of...
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    [Biology] Nervous System

    Okay, the fatty myelin sheaths that wrap around axons do not allow the sodium ions to diffuse into the neuron, thus inhibiting a neural response. But, there is a way to get around that. The gaps, or nodes of Ranvier, allow the impulse to travel hundreds of times faster because many parts of the...
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    Help Determining (Dis)Continuity of a Trig Function

    I'm having problems finding whether or not a trig function is discontinuous or continuous. Besides graphing, I don't understand how you can tell. How do you know if a trig function is continuous or not, for the 6 basic functions?
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    Top 10 Emerging Diseases

    You made a good point. AIDS has been known for a long time. I have a brand new textbook (recently published), and it states this: "SARS, AIDS, hepatitis C, and viral encepalitis are examples of recently identified diseases that cause sever mortality and morbidity and are currently on the rise."...
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    Top 10 Emerging Diseases

    Why isn't it? The definition in my microbiology book is a disease 1) that has been recently identified, 2) that is reemerging and becoming more common, or 3) that is changing and becoming resistant to drugs. Am I misunderstanding the definition?
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    Top 10 Emerging Diseases

    Hi, I'm trying to find the top 10 emerging diseases in the US and the top 10 worldwide. I've found lists of many diseases, including AIDS, SARS, etc., but I haven't been able to isolate the top 10 for either category. Does anybody know a site that provides a definite list for each category...
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    Freezing point estimation

    I don't know the freezing point, but you can probably find a table that gives you that data so you can check your answers. Also, you use t = 273.15 Kelvins because that is, in basic terms, the accepted unit of temperature in chemistry/physics, etc. You will use Kelvins in the gas laws...
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    More Word Problem - Please Help -

    Well you know a few things. You just have to put it all together. 1) The patient must receive AT LEAST 30 units. You use the "greater than or equal" sign. 2) Each pill provides 3 units of medicine. Thus, each type of pill is multipled by 3. 3) You need twice as many red pills as yellow...
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    Lateral Area of a Pyramid

    This problem is really getting to me, and I don't know why... INfo: Pyramid, Side length = 300 ft, perpendicular height = 321 ft, and slant height = (work shown later) 1. Find the slant height. Round your answer to the nearest whole number. (slant height)^2 = (height)^2 + (.5(side))^2 =...
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    Conic Sections

    Yes, I've tried completing the square. I got a strange answer, however. I'm just going to have to ask my teacher for help. And thank you, master_coda, for help with number 2. The equation turned out to be 10^2/20^2 + y^2/12^2 = 1; where y = 10.4, which is the needed answer.
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    Conic Sections

    Here are two problems that stumped our entire precal class. And we have a test soon, so I would like to be able to know how to work these type of problems. 1. Write the equation of the hyperbola, x^2 + 4xy + y^2 - 12 = 0, in standard form. Okay, I know the formula needs to be x^2/a^2 -...
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    Vertical or Horizontal ellipse?

    If the value under y^2 is greater, then it's going to be a vertical ellipse. If the value under x^2 is greater, then it's going to be horizontal. You can check by graphing and calculating the lengths of the major and minor axes. That should help you too.
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    Photon Emission Rate and Optics Questions

    Oh, and our textbook is a Conceptual PHysics book, and there is no math in it. so I can't really consult it. This isn't the first time I've received random problems I didn't know how to do.
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    Photon Emission Rate and Optics Questions

    I'm reading. I was able to solve the other 5 problems that came with these. But, these questions are due tomorrow at the beginning of class... Which means, we're not going over them.
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    Photon Emission Rate and Optics Questions

    I'm really lost on these 3 questions. My physics teacher decided she was sick of thermodynamics and gave us this packet over material we haven't covered yet, but she expects us to get it without any problem. I'm really stuck on these: 1. Assume that sodium produces monochromatic light with a...
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    Parabolas math problem

    Thank you for the help. I think that's right. Solving for y, it would be 1.25, which is the answer. I just didn't know how to come to it and show my work. Thanks again.
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    Parabolas math problem

    Actually, I figured it out. x^2 = 4ay, and a must equal 5 because the focus is (0,5). That means teh equation is x^2 = 4(5)y or x^2 = 20y. What I can't figure out is part B: If the dish is 10 feet wide, how deep is it? I have never had a question like this before. How do you know how...
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    Parabolas math problem

    I'm having difficulty with this question. All help is appreciated. *The cross section of television antenna dish is a parabola and the receiver is located at the focus. A. If the receiver is located 5 feet above the vertex, assume the vertex is the origin, find an equation for the cross...
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    Speed of Alpha Particle

    An alpha particle is accelerated to a velocity v in a particle accelerator by a potential difference of 1200 V. Which of the following potential differences would be needed to give the alpha particle twice the velocity? A. 7200 V B. 4800 V C. 4100 V D. 2400 V E. 1700 V At first, I...
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    How to graph conic?

    Try to isolate either x or y. That way, it will be easy for you to find the plotted points. If, however, you have a program, like Geometer's Sketchpad, you can plot that graph without doing anything.
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    Did I do this correctly?

    Ok, thank you for checking.
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    Did I do this correctly?

    Calculate the force of gravity on a 1-kg mass if it were 6.4 x 10^6 m above Earth's surface (twice Earth's radius). Known: Mass of object 1 = 1 kg Mass of Earth = 6 x 10^24 kg Earth's radius = 6.4 x 10^6 m; 2x this is 1.28 x 10^7 m G = 6.67 x 10^-11...
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    Coefficient of Sliding Friction

    Does anybody know a website that gives sliding friction (blocks on planes, etc.) example problems? I am trying to figure out how to calculate the coefficient of sliding friction, but I'm having problems doing so. I know the general equation is: coefficient of sliding friction = friction...
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    How to find currents and voltages in circuits

    Could you creat a drawing in paint, so the image would be easier to work with? That way, you might receive more help.
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    How fast will a car be moving at a certain point?

    I have a problem I'm trying to figure out. To see the problem and picture, please go to problem #10 at this site: The problem says, A roller coaster car moves along a track as shown. At point A, the car is moving with a speed of...
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    What Am I Doing Wrong?

    Oh, thanks. I forgot to use the negative sign for force heading in the opposite direction. Thanks again for that help.
  27. V

    What Am I Doing Wrong?

    I have a few questions that I got wrong, and I'm trying to find out what I did. All help is appreciated. 1. A cube of aluminum has side length .10 m. It is dropped into a deep swimming pool of water withd ensity 1.00x10^3 kg/m^3. The cube comes gently to rest at the bottom of the pool. If the...
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    Math Question, badly.

    After changing n to (n+1), you get: (n+1)^2 = n(n+1)/2 + (n+1)((n+1)+1)/2) = (n+1)^2 = (n^2+n)/2 + (n+1)(n+2)/2 = (n+1)^2 = (n^2+n)/2 + (n^2+3n+2)/2 Since they have common denominators, we can add the right side together: = (n+1)^2 = (2n^2 + 4n + 2)/2 = (n+1)^2 = (2n+2)(n+1)/2...
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    Homework Help, Please

    I need some help with these two problems: 1. A wheel of radius 30 cm has forces applied to it as shown in the figure below. Find the torque produced by the force of (a) 4 N (b) 9 N (c) 7 N (d) 6 N. See attachment for figure. (a) = _____1.2 N*m_____ counterclockwise? (b) = _____2.7 N*m_____...
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    Potato gun

    We just made a potato gun in our physics class... Ours was made of white PVC pipe (simply because that's what Home Depot had and we didn't feel like changing anything). Black is suggested in many websites, though, so it's a good idea. As for the propellant, we used hairsrpay, but another team...
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    Momentum and Breaking force of car

    I have some questions as homework, and for some, it would be nice to know whether or not my answers are wrong. I need guidance on one of the questions, and I have no idea where to start on other. Our physics teacher is making us start from the back of the book (nuclear physics) and move...
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    Coefficient of Sliding Friction Lab

    I have to do a lab this grading period, which I chose out of a hat. The lab is on the coefficient of sliding friction. I have to have an experiment, but I do not want to just have different objects slide off a ramp or anything simple like that. Does anybody have a good experiment idea that...
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    Show that the force applied by each rope

    Here's my guess: -T_1\cos(40)+T_2\cos(40)=0 T_1\sin(40)+T_2\sin(40)-400N=0 Those two are equations above are for your x- and y-coordinates. The force must equal zero. The first equation simplifies into: T_1=T_2\cos(40)/\cos(40) *T just stands for tension of cables 1 and...
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    The Physics Behind a Potato Gun

    I have to tie the construction and dynamics of a potato gun with one chapter from my physics book. That's fairly hard to do because a potato gun has much to do with more than one chapter, but my teacher just wants one... Does anybody have an idea on what the best chapter would be? I have...
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    Internal energy of gas homework

    Try using this link. It sends you to a problem on a college physics site; your question is very similar to the example found on the website. I hope it helps. [Broken]
  36. V

    Finding Zeros of a function

    Oh, well I live in TN... Is the person you knew Russian? I have never met anybody else with my name before. Most people think it's weird; it's definitely not common here.
  37. V

    Finding Zeros of a function

    Nope... What makes you say that?
  38. V

    Finding Zeros of a function

    x^4-25=0 x^4=25 x^2=5 x=+-/sqrt{5}
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    Help Describing Vectors

    I am having problems with describing vectors. I understand the part that vectors have magnitude and direction, but that's not the part I'm having issues with. I can't look at a figure and find out whether or not the vector is, for example, 30 degrees south of east or 30 degrees east of south...
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    Work done by an ice cube

    Thank you for all of your comments. I'm just glad to know I'm on the right track.
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    Work done by an ice cube

    My teacher gave us a hint that the process was only isothermal... My guess then is that the volume does not vary. And the problem with the mass doesn't surprise me. I took the value from teh Periodic Table and divided it by 1000. I didn't take into account the volume. I'm not sure how I would...
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    Help! Can't do conics!

    This should give you 2x^2 + 12x + 18. I hope I'm doing this right...
  43. V

    Help! Can't do conics!

    All you know is 2x^2 + 12x + ?. Factor out the two to make it easy. Now you have 2(x^2 +6x + ?) Then you can fill in the square by making it 2(x^2 + 6x + 9) or 2(x+3)^2
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    Help! Can't do conics!

    1. 2x^2 + 12x + 18 which is equivalent to 2(x+3)(x+3) + y^2 - 2y + 1 which is equivalnt to (y-1)(y-1) = -15 + 18 +1 2. Your equation is 2(x+3)^2 + (y-1)^2 = 4 3. Divide each side by 4. Now you have: 2(x+3)^2/4 + (y-1)^2/4 = 4/4 4. Now, your final product is: (x+3)^2/2 + (y-1)^2/4 = 1 Is...
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    Work done by an ice cube

    Hi, I need some help with my thermal physics. I posted these questions on the high school forum (I'm just a junior in high school), but my physics teacher takes questions out of college-level books, so I thought it would be more appropriate if I posted here. The two questions are: 1. An...
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    Thermal Physics Help Needed

    Oh, really? I'm just using the formulas my teacher provided... I would just like to know whether or not these solutions are possible. My physics teacher says she's not too picky about the final answer; she just wants to see how we got to our solutions. So, I would mainly like to know whether...
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    Thermal Physics Help Needed

    Hi, I'm a high school physics student, and I'm having problems with two questions: 1. An aluminum cube 20 cm on a side is heated from 50° C to 150° C in a chamber at atmospheric pressure. Determine the work done by the cube and the change in its internal energy. If the same process was...