Recent content by capandbells

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    What is the tension in the rope used to pull two blocks with friction?

    Oh... ok. So L = (c - a) + (c - b) and differentiating twice, 2A = a_a + a_b. Solving for T we get T = 2 \frac{m_a m_b}{m_a + m_b}A + f
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    What is the tension in the rope used to pull two blocks with friction?

    I guess that is the part that I am having the most difficulty with. I don't see any way to incorporate the acceleration applied to the pulley. The only thing I can think of is that accelerating the pulley to the right is the same as subjecting the pulley to a gravitational acceleration to the...
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    What is the tension in the rope used to pull two blocks with friction?

    Homework Statement Mass Ma lies on top of mass Mb, as shown. Assume Mb > Ma. The two blocks are pulled from rest by a massless rope passing over a pulley. The pulley is accelerated at rate A. Block Mb slides on the table without friction, but there is a constant friction force f between Ma and...
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    Discovering Alternative References for Studying Srednicki's QFT

    I and most of the people I've talked to about this agree that the best way to learn QFT is through a combination of Zee's QFT in a Nutshell and Peskin & Schroeder. The former gives lucid explanations of what's happening conceptually, which is a huge benefit because a lot of the trouble people...
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    Studying Is it OK to ask professor to use different textbook?

    What textbook would you rather be using? And if you know enough about solid state physics to know the material it leaves out, why are you taking an introductory solid state class?
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    How to define the Hamiltonian phase space for system?

    The \mathbb{R}^2 doesn't mean squared real numbers. It means the set of order pairs of real numbers (x,y), where x and y are real numbers. So (q,p) \in \mathbb{R}^2 just means points in phase space are composed of pairs of real numbers q and p.
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    Schrodinger equation for three dimention?

    Close. In three dimensions the time-independent Schrodinger equation for the wavefunction (in Cartesian coordinates) is -\frac{\hbar^2}{2m}\nabla^2\psi (x,y,z) + U(x,y,z)\psi(x,y,z) = E\psi(x,y,z) where \nabla^2 is the Laplacian. You could also express this in coordinate systems other than...
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    Schools Question about physics grad school.

    I'm in my first year of grad school right now. We don't exactly have tutoring, but the TAs hold discussion sections and office hours. This is fortunate because the professor for my classical mechanics course can be pretty confusing, but the TA for the class is brilliant, lucid and very enthusiastic.
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    What is the Inner Product of <+z|+n>?

    Yeah, that's all you need.
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    What is the Inner Product of <+z|+n>?

    It seems to me that it's ALL of the issue. The inner product <z+|n+> is all you're asked to compute.
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    Linear Collisions; Conservation Law

    20 cm/s would be 0.20 m/s, not 0.02 m/s
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    Instantaneous Speed in a time interval

    The first part of your answer was correct. If the ball gains the same amount of speed in each time interval, the acceleration is constant. But if the speed is increasing, does it follow that the distance traveled in each time interval would be the same?
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    Do I have the drive to be a Physicist?

    You can spend the rest of your life trying to understand why people (including you) think the things they do and behave the way they do, and you'll still come away confused. That's a big part of what life is.
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    How can we know initial state of a particle

    If you can get ahold of Ballentine's QM book, Ch. 8 explains this well.
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    Staying motivated after graduate acceptance

    Yes, I'm doing something I like a lot. I'm very excited to be going to graduate school. (We'll see how I feel about that after the first couple of months though... :p) Doing well at what? I was highly motivated to study physics because I love physics and I wanted to be able to keep doing it...
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