Recent content by Artaxerxes

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    What Is Electron Transmission Spectroscopy?

    Can anyone explain what "Electron Transmission Spectroscopy" is? Or give a link where I can get an explanation?
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    Graduate Why are eigenstates important in the treatment of atomic systems?

    Let's consider the hydrogen atom with one electron. If we observe the energy the result is always one of the eigenvalues even if the statefunction is arbitrary. I accept that. But why is the atom always treated as if the electron is in one of the eigenstates? Why is the statefunction always...
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    Graduate Integrate cos(x^5): Solve \int \cos x^5 dx

    Thank you!
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    Graduate Integrate cos(x^5): Solve \int \cos x^5 dx

    Can you solve this \int \cos x^5 dx ?
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    6 problems on Conservation of Energy

    Problem 6 Potential energy at start = energy loss due to friction + potential energy of spring at the moment when the body is at rest mgh = \mu mg L + \frac12 k x^2
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    6 problems on Conservation of Energy

    Problem 5 (a) For this motion, determine the change in the block's kinetic energy Calculate kinetic energy with initial speed v0=8 m/s and then with finel speed v=0. The difference is what they ask for. (b) For this motion, determine the change in potential energy of the block-Earth...
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    6 problems on Conservation of Energy

    Problem 4. (a) String potential energy is U_s =\frac12 \cdot k \cdot x^2 Kinetic energy is KE = \frac12 \cdot m \cdot v^2 U_s=KE should give you v. (b) Energy lost due to friction is W_{fr}= F_{fr} \cdot x = \mu \cdot mg \cdot x The friction force is (almost) independent of speed -...
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    6 problems on Conservation of Energy

    I see that I made a mistake in problem 1. I didn't put the mass into the formula for the kinetic energy. Should be T_A = \frac 12 \cdot m \cdot v^2. :blushing:
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    6 problems on Conservation of Energy

    Problem 3. Use these general relations Hooke's law F = -(k/L)x Gravitation on body F = mg Potential energy in cord U = ½*(k/L)x^2 Potential energy of body U = mgh Use Hooke's law and "hanging at rest from a 5.00 m length of the cord, he finds that his body weight stretches it by 1.30 m"...
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    Graduate Do Newton's Three Laws of Motion Hold True in Quantum Physics?

    The first law (a = 0 if f = 0) is a special case of the second law (f = ma).
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    6 problems on Conservation of Energy

    Problem 2. (a) Conservation implies loss of potential energy equals gain of kinetic energy: m_1gh - m_2gh = (m_1 + m_2)v_{hit}^2/2 Solve for "hit speed" v_{hit}. (b) Consider only m_2 m_2 v_{hit}^2/2 = m_2g (y_{2,max} - h) Solve for maximum height y_{2,max}.
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    6 problems on Conservation of Energy

    Problem 1. Total energy, E, equals potential energy, V, plus kinetic energy, T, E = V + T. Conservation of energy implies total energy is constant, E_0 = E_A = ... E_0 = V_0 + T_0 = mgh + 0 = mgh E_A = V_A + T_A = mg\cdot2R + T_A Now you can solve for T_A But you also know...
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    Basics: Object on Incline, Forces (Im Hopeless) Help

    http://www.pha.jhu.edu/~broholm/l10/node2.html If you use LaTeX the text will be more legible. It's easy, and it's fun. Some remarks... If you choose x to be parallel and y perpendicular to the incline: F_x = mg \sin \theta - \mu F_N F_y = F_N - mg \cos \theta If no motion in...