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    Fe-N bond!

    I've been searching far and wide and simply cannot find any info on the BOND ENERGY of a Fe- N coordinate-covalent bond, like that found in the heme group of haemoglobin. it looks like this: ....... N ....... | N -- Fe2+ -- N ....... | ....... N...
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    Haemoglobin properties.

    hello everyone. I was wondering if anyone knew a site that would tell me the properties of haemoglobin such as its boiling point, melting point, etc.. I can't seem to find any. I am doing a project on the "heme group" and I need to find properties such as weight, bp, ml, etc for heme group...
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    Nitrogen Valences?

    Hey everyone I am confused as to the structure of a heme molecule. A picture of it is shown here: I understand the heme group is largely a porphyrin molecule. The 4 Nitrogens are coordinate-covalently bound to the central Iron atom. The...
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    Ballistic Pendulum!

    Hi all We are doing a physics lab where we lift a pendulum to a certain height, let go of it, and the pendulum strikes a physics cart on a track. A lightgate then measures the velocity of the cart. We need to figure out the speed of the cart given the distance the pendulum is raised by...
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    Combination Lock

    Hey everyone I have this for Discrete homework: A lock has the numbers from 0 to 59 .......A combo is made up of 3 numbers.......How many combos are possible if the 2nd and 3rd numbers have to differ by at least 3 The answer is whatever 60 times 58 times 57 is I know why the 60 is...
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    Motor and Battery!

    Hey everyone, I built a motor for my physics exam....and it works extremely spins extremely fast and there are sparks galore on the commutator. I have it attached to a 6V lantern battery (the ones a bit bigger than your fist). How long can I expect the battery to keep...
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    Ohm's law

    When plotting potential difference VS current (volts VS amps) does one explain the intercept at (0,0) ? Is it because without potential difference you can't have current and vice versa? Is that true all the time? Thanks
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    Resistor Tolerance/Error

    Hey everyone. I am doing an Ohm's law lab where there is a variable source, a fixed resistor, a voltmeter across the resistor, and an ammeter in series with the resistor. The fixed resistor is an unknown value but has a tolerance of 5% You need to figure out its value by plotting...
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    Work Problem (easy but weird)

    This seems easy but I'm not getting the right answer! The question: A 0.5 kg ball is thrown into the air. At a height of 20m above the ground, it is travelling at 15 m/s. a)How much work was done by someone at ground level throwing the ball up into the air Ok, for a), Work=Force x...
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    MagLev model?

    I am doing a project for my physics course....I have to design a device that uses electromagnetism. I'm thinking of doing something "different" rather than the boring bells/radios etc.. Would a small-scale model of a maglev train be feasible in everyone's opinion? I am planning to build...
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    Diagonal Frog

    I love Kai Krause's quote "A good analogy is like a diagonal frog" me it's one of those "astronomically small" or "authentic replica" Is that why it's so popular...because it's a clever oxymoron...or did this guy Kai Krause have another intent for the quote that I...
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    Population problem

    -------------------------------------------------------------------------------- Hi everyone I'm having trouble with this problem, while preparing for my calculus test this Monday....could anyone help me figure out the solution....I know that I must use the formula P=P(original)e^kt...
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    Fascinating Time-Travel Paradox

    I love this time-travel paradox Suppose you get visited by a man claiming to be the future you. he tells you the plans to build a time machine, and tells you that you must build it, and use it to tell your younger self about the invention (like he is doing now) You then grow up, and use...
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    The constant e

    I am currently learning about logarithms and I understand that Log base e (or Ln) comes up quite often in solutions of logarithms However, I also heard that it is a number that comes up often in nature Are there any good examples of "e" in nature? Anton
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    The Matrix Mistake?

    "The Matrix" Mistake? In the movie "The Matrix", Neo has feelings that his world is not real. He discovers he is right when he meets Morpheus, who transports him into the “real world” My problem is that Neo all of a sudden stops wondering , and blindly accepts the “real world” as...
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    Why do people ask why life exists?

    People always say "It's so surprising that we exist" or "It's so surprising that life exists in such a chaotic universe".....There was even an article in Discover magazine a while ago where an Astrophysics professor was discussing how the Universe has a series of constants and properties, that...
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    Curious question about Magnets!

    When playing around with magnets, one can notice that they attract objects from a distance. No only that, but they can also attract quite heavy objects many, many times in a row. Where does the energy that moves the objects come from/stored? Does it ever "run out"? My guess is that magnets...