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Can someone help me? take home physics final, we can use any resource possible. Help!

  1. Mar 13, 2009 #1
    there are pictures and hints missing, view fullo version in the attached file.

    Below is a short-story of a scenario where you are president of the universe Zaphod Beeblebrox.

    In order to answer several of the questions below you will need access to appropriate references. You may use any reference source you desire to complete this exam and you may collaborate with anyone while working on it. However, your final turned in solutions must be entirely your own work and, as always, you must always clearly show you thinking and how you derived your answers.


    In order to aid the plot of the story, I’ve taken some “literary license” in the physics of the story. I’ve added some footnotes at end to assist you in these situations and to give you hints in some areas. Have fun!


    Your name is Zaphod Beeblebrox, and you are President of the Universe. You are aboard SpaceForce One headed toward Congress. Congress is an artificial ocean planet that utilizes a nearby compact gamma ray emitting black hole as a power and transportation source. You have been approaching Congress for a couple of weeks and obtained the below data.

    1. Using the below data find the mass of the Blackhole. In order to answer this question, you will need to study the concept of “Reduced Mass”.


    You come to a landing on Congress. Actually, it was more a splash-down than a landing as Congress is made up of mostly ocean. Consulting your favorite book, you read that Congress has a radius of ro= 9•105 meters. Due to a large core of the element Administratium the average density of the planet ends up giving it a surface gravity of 25m/s2. The atmosphere is mostly Xenon with a density profile that looks like where 0 is the standard density of dry Earth air at Earth sea level.
    2. What is the total mass of the atmosphere on this planet?
    3. SpaceForce One is a perfectly spherical ship of mass 1.5•106kg and Radius 25meters. The ocean of Congress is pure fresh water. How high above the surface of the water does your ship float?
    4. At what frequency does your ship bob? (As always, explain any approximations you make.)
    5. You speed across the surface of Congress at a speed of 0.1c. Behind you there is a radio tower emitting radio waves at 550 on the AM dial, ahead of you is an identical radio tower emitting identical radio waves. You hear a beat pattern due to the Doppler Effect as you travel directly away from the first tower and directly toward the second tower. Meanwhile, reporters sitting stationary with respect to the two radio towers know that there “dead-zones” between the two towers. What is the period between beats you hear from your point of view? How long does it take for you to travel between the dead-zones from the reporters’ point of view? Compare these two times and comment upon your result.

    You come to the dock of a small island and find yourself surrounded by reporters. The reporters of Congress however are only 20cm tall and look slightly like a Peruvian puma. You say “Dude!” None of the reporters seem to hear you. You give yourself a dopeslap as you remember that you’ll need to speak at a different pitch so that these puma-like reporters can hear you. You can’t remember of the top of your heads (you have two of them) at what frequency they speak, so you look at them, consider what the atmosphere is make out of, do some calculations and choose a frequency at which to say “Dude!”.

    6. What frequency do you choose and why did you choose it?




    The real purpose you came to Congress and actually the real reason you became President of the Universe in the first place, was to steal the prototype ship “The Heart of Gold”. The Heart of Gold travels via a “Planck Drive”. The propulsion system works by changing Planck’s constant in a localized area. The great thing about a “Planck Drive” is that you can get from point A to point B without ever having to travel anywhere in between. You have positioned a 2nd Blackhole a distance of exactly 40 light-years away from Congress’ Blackhole. These two Blackholes can act as a resonant matter wave “box” where the Event Hhorizon of each Blackhole acts as the end of a quantum box.

    7. If the Heart of Gold has a mass of M=5.0•109kg, a diameter of 100 meters, and velocity v=142km/h (88mph), to what value of do you need to adjust Planck’s Constant in order to spontaneously teleport yourself into impregnable “Fort Knox” that happens to be exactly 10 light-years away from Congress’ Blackhole at this moment?

    You successfully arrive at “Fort Knox”. Fort Knox consists of two rings attached together as shown in the picture. Fort Knox has a mass of 3•109kg, a radius of 200 meters and has its mass even distributed along its rings.

    Before docking, your ship has an artificial gravity of 9.8m/s2 for a person standing on the equatorial ring of the Heart of Gold. The people of Fort Knox (who happen to resemble small white Earth-mice) like to keep their gravity at 25m/s2. No thrusters will be used to change the angular speed of either ship in the docking process.

    8. What will the artificial gravity be in both ships after the docking process?
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     

    Attached Files:

  2. jcsd
  3. Mar 13, 2009 #2

    cristo

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    Re: Can someone help me? take home physics final, we can use any resource possible. H

    You need to show some work before we can help with your homework.
     
  4. Mar 14, 2009 #3

    Avodyne

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    Science Advisor

    Re: Can someone help me? take home physics final, we can use any resource possible. H

    Zaphod Beeblebrox was President of the Galaxy, not the Universe! See http://en.wikipedia.org/wiki/Zaphod_Beeblebrox#Achievements

    I suggest refusing to answer all questions on that basis.
     
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