Recent content by whyme1010

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    Are there paid internships in research for good causes in undeveloped countries?

    Hello, Does anyone know if any companies working for good causes (water filters, disease control, agricultural improvements) in undeveloped countries have paid internships for the summer (if not paid, at least room and board). Actually I'll even take good unpaid internship opportunities. I'd...
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    What Are the Top Condensed Matter REU Programs?

    I'm looking for an REU program to do over the summer in hard condensed matter. Some connection with quantum information/ quantum computing would be awesome, but not necessary. Does anyone have any recommendations?
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    Should a first-year be doing research?

    Hello, I'm a first-year undergrad at the University of Chicago. I'm having difficulty gauging when I'm supposed to get into research. I read some threads about the difficulties in getting into a REU over the summer- especially for students at large research universities (and the fact that...
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    Prove that a cylinder has the least moment of inertia

    Not sure if this is correct. Or even how to write it up.
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    Prove that a cylinder has the least moment of inertia

    Well to prove that each cross section disc has to be a circle, I would start by assuming that it was a circle to start with. Now take any infinitesimal amount of mass on the circumference and move it to a radius greater than that of the circle. by the way moment of inertia is defined, this would...
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    Prove that a cylinder has the least moment of inertia

    well a double hemisphere would have the least moment of inertia. so I'm pretty sure it's asking for a uniform cross section body. But then this entire question is trivial.
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    Prove that a cylinder has the least moment of inertia

    Homework Statement Consider a solid homogeneous object taller than its wide, with the top and bottom parallel. Prove that the shape with the lowest moment of inertia about an axis through the object is a cylinder with the axis through its axis of symmetry. density, mass, and height are...
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    Prove 2ab<= a^2+b^2 using order axioms

    yeah. I also solved this by using three lemmas. =) Don't know how to close the thread though.
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    Proof by induction: multiplication of two finite sets.

    yeah, but how do I prove that if it is true for the n+1 case, it is also true for the m+1 case. and what if m+1 and n+1 are occurring at the same time? I guess what I'm asking is, if I prove it true for the n+1 case (which is pretty easy), then how do I show that this means I can add one...
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    Proof by induction: multiplication of two finite sets.

    Homework Statement prove by induction that if A and B are finite sets, A with n elements and B with m elements, then AxB has mn elements Homework Equations AxB is the Cartesian product. AxB={(a,b) such that a is an element of A and b is an element of B} The Attempt at a Solution...
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    Prove 2ab<= a^2+b^2 using order axioms

    well then I can just prove that a^2 is always greater or equal to zero. a>0 Then a(a)>(a)0 a^3>0 a<0 a+(-a)<0+(-a) 0<-a -a(0)<(-a)(-a) 0<(-1)(-1)(a)(a) 0<a a=0 a(a)=0(a) a^2=0 So a^2 >=0
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    Prove 2ab<= a^2+b^2 using order axioms

    Homework Statement prove 2ab<= a^2+b^2 using order axioms Of course use of other basic axioms for real numbers are also okay. Homework Equations axioms for set of real numbers. The Attempt at a Solution The easy way to do this would be just subtract 2ab from both sides, factor...
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    Future Astrophysicist: From Questbridge Scholar to Top Grad Schools and Beyond

    I'm a high school senior in New York City who got into the University of Chicago through Questbridge- a scholarship program. It pays for everything- dorms, tuition, insurance, travel, etc. I want to major in physics with a concentration in astrophysics. I'm pretty certain its what I want to...
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    Why do meteors burn up in our atmosphere / why are they moving so fast?

    Okay, so stuff reaches terminal velocity because the drag force is a resistive force proportional to the velocity of the object moving through it. F= -bv, and b can be some function but usually it can be represented more simply. Terminal velocity is reached at around five or four tau- I forget...
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    Pressure at points on the same horizontal plane

    Pressure is rho g h right? So the water in the middle has pressure applied on it from atmosphere as well as the water above it, while the water to the left only has pressure applied to it by the water above it. Pressure does not spread laterally. If you push on a piece of paper, the paper...
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