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  1. E

    Length contraction of a square

    If you have a drawing of a square (labeled ABCD starting at lower left and going clockwise) and it is first at rest in an inertial frame. When this square moves, length contraction changes its shape. In each of the following three situations the speed is the same, and the velocity is in the...
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    Neurons and axons

    What problems does a neuron need to overcome to maintain the health and growth of the axon? I thought it has a problem with axon's length? Another question is: How would you estimate the muscle mass of a person? I know that muscle does not float, but adipose tissue does. Would I just...
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    Nitrogen Fixation

    I've done some browsing on Gleocapsa and found out that it is unicellular. I can find them in wet mounts, ponds, moist soil, damp or wet areas. I also found out that Gleocapsa is a nitrogen fixer. My question is, since Gleocapsa is surrounded by a clear, gelatinous coating which makes one or...
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    Sordaria Questions

    The following is an assignment for homework for an intoductory biology class in college: Sordaria is a member of the ascomycete fungi, a group often used in genetics experiments. Yet, Sordaria is haploid. How can a haploid organism be used to test genetics problems when such things as...
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    Meiosis problem help

    Hi, I'm doing some studying before the exam and I'm not clear about a certain concept regarding the following question: "Select the choice that is NOT true. Crossing over A. Occurs between non-homologous chromosomes during prophase I of meiosis. B. Occurs during prophase I of meiosis...
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    Mating, how many offspring?

    Bbss with bbss, what to do? In goats, black color (B) is domnant over red (b), and solid color (S) is dominant over spotted (s). If the offspring between Bbss and bbss individuals are mated with each other, what fraction of their offspring will be expected to be black and spotted? Assume these...
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    Help with understanding about Sordaria

    Please help me. I know that Sordaria is a member of the ascomycete fungi, a group often used in genetics experiments. Yet, Sordaria is haploid. How can a haploid organism be used to test genetics problems when such things as crossing over require meiosis as the cell goes from a diploid to a...
  8. E

    Conversion Problem

    A cube with a volume of one cubic centimeter (1 cc) has equal sides of 1 centimeter squared with a total surface area of 6 square centimeters (= 6 cm2 or 600 mm2). Dividing the same volume into 1000 cubic millimeter units would lead to a total surface area of ? A. 6 cm2 B. 6 mm2 C. 60...
  9. E

    Finding the change of internal energy

    In moving out of a dormitory at the end of the semester, a student does 2.69 x 104 J of work. In the process, his internal energy decreases by 5.52 x 104 J. Determine each of the following quantities (including the algebraic sign): (a)W, (b) delta U, and (c)Q. I get the following using...
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    Finding speed using conservation of mechanical energy

    In preparation for shooting a ball in a pinball machine, a spring (k = 675 N/m) is compressed by 0.0650 m relative to its unstrained length. The ball (m = 0.0585 kg) is at rest against the spring at point A. When the spring is released, the ball slides (without rolling) to point B, which is...
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    Finding the forces in equalibrium

    A woman who weighs 476 N is leaning against a smooth vertical wall at an agnle 60 degrees above the horizontal. Find (a) the force FN (directed perpendicular to the wall) exerted on her shoulders by the wall and the (b) horizontal and (c) vertical components of the force exerted on her shoes by...
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    Finding the angle

    A uniform board is leaning against a smooth vertical wall. The board is at an ange above the horizontal ground the coefficient of static friction between the ground and the lower end of the board is 0.650. Find the smallest value for the angle such that the lower end of the board does not...
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    Finding the tangential speed Help

    Finding the tangential speed.... Help i got it, it I shouldn't have doubled my time. My answer is 4.65 m/s right?