Recent content by SA32

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    Chemistry - interpreting Fractional Distillaion.

    I did fractional distillation to separate two solvents in my chem lab last week and I was just wondering if someone could check my thinking. So for the first little while after the distillation began, no solvent collected in the receiving flask because the temperature was still making its way...
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    Magnetic forces exerted by current-carrying wires

    Okay I think I see, the top wire is parallel to each of the bottom wires, just the force from each has both an x-component and y-component. But the x-components cancel out and so the net magnetic force on the top wire is just straight up, isn't it? And looking again at the equation for the...
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    Magnetic forces exerted by current-carrying wires

    Homework Statement The figure (http://img.photobucket.com/albums/v80/northerndancer/thefigure.jpg?t=1173558797 ) is a cross section through three long wires with linear mass density 50 g/m. They each carry equal currents in the directions shown. The lower two wires are 4.0 cm apart and are...
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    Which Acids/Bases React with Water to Produce Non-Neutral Solutions?

    Forgot I posted this! Thanks for your response. :)
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    Which Acids/Bases React with Water to Produce Non-Neutral Solutions?

    Homework Statement Which of the substanced KCN, NaF, KBr, LiCl, and NH4Br will react with water to produce non-neutral solutions? a.) KCN, LiCl and NH4Br b.) KCN, NaF and NH4Br c.) NaF, LiCl and NH4Br d.) NaF, KBr and NH4Br e.) KCN, KBr and LiCl Homework Equations The...
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    Freefall motion: velocity, acceleration, momentum, kinetic energy

    Thanks so much! Now I think I can use the kinematics equation to find the relations between the heights, and do likewise for the kinetic energy question. Cool.
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    Freefall motion: velocity, acceleration, momentum, kinetic energy

    Homework Statement Consider three ball bearings, one with a mass of 8 g, one with a mass of 16 g and one with a mass of 32 g. a.) What heights should the three ball bearings be dropped from so that at impact all three ball bearings will have the same velocity? b.) What heights should the...
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    Biology (translation) extremely confused, final is tomorrow

    Homework Statement 8) Suppose the following DNA sequence was mutated from 5'-AGAGAGAGAGAGAGAGAGA to 5'-AGAAGAGAGATCGAGAGA. What amino acid sequence will be generated based on this mutated DNA? A) glu-arg-glu-leu-leu-leu B) ser-leu-ser-leu-ser-leu C) ser-ser-leu D)...
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    Integrals and Derivatives: Solving Problems with Limits and Rates of Change

    Homework Statement In the attachment: 5aef, 6abc The Attempt at a Solution 5a.) I started by dividing the question into two integrals: the integral of 2sin(x) evaluated from 0 to pi/4 minus the integral of 4sec2(x) evaluated from 0 to pi/4. Then the anti-derivative of 2sin(x) is -2cos(x)...
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    Friction and torque of ladder resting on wall

    Ahh, that makes sense. Thanks!
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    Friction and torque of ladder resting on wall

    Homework Statement A uniform ladder with mass m2 and length L rests against a smooth wall. A do-it-yourself enthusiast of mass m1 stands on the ladder a distance d from the bottom (measured along the ladder). The ladder makes an angle x with the ground. There is no friction between the wall...
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    Chemistry - energy and photons, Lewis structures

    1.) Thanks, that helps! 2.) The diagram in the attachment had O with two lone pairs double bonded to C double bonded to N with two lone pairs and a formal charge of -1 on N. Thanks for the help.
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    Chemistry - energy and photons, Lewis structures

    I'm doing a practice exam that I have answers to, but I'm not sure how to go about getting to the right answer for some. Homework Statement A nitrogen laser produces pulses of light of wavelength 337.1 nm. If each pulse contains 10.0 mJ of energy, how many photons are contained in one...
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    Calculus I - max/min, concavity

    This problem is really frustrating me. Any help is appreciated! Answer the following questions for the function f(x) = \sin^{2}{\frac{x}{6}} defined on the interval [-6π + 0.8, 6π/4 - 0.3]. A. f(x) is concave down on the region ____ to ____. B. A global minimum for this function occurs...
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    Forces - friction, centripetal

    Oops! I wasn't even thinking of that, my bad... Yeah, I think you're probably right, I'm just worried that the solutions are a bit brief compared to what might be expected on an exam. Maybe I'll just talk to my prof about it. Centripetal acceleration is toward the center of the circle...
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