Recent content by pearapple

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    Quantum Mechanics - Superposition of Wavefunctions?

    Thanks! I believe you're right. In general, I don't think p3 = p1 + P2. I don't think I could explain why though. I just don't see WHY those would be equal, because although state 3 is a superposition, it is still a new state is it not? Is there some situation in which p3 = p1 + P2 is true?
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    Quantum Mechanics - Superposition of Wavefunctions?

    Homework Statement The wavefunction for a particle in one dimension is given by ψ1. Another state the particle may be in is ψ2. A third state the particle could be in is ψ3. Looking at the wavefunctions, ψ3 is ψ1 and ψ2 added together. Is the probability of being in a given interval in...
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    Let A and B be relations on the set C = {1,2,3,4,5,6}

    Perfect, thanks!
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    Let A and B be relations on the set C = {1,2,3,4,5,6}

    So would it be: x RUS y if (x R y or x S y) ? And the condition for symmetry is if x RUS y then y RUS x?
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    Let A and B be relations on the set C = {1,2,3,4,5,6}

    Homework Statement Let A and B be relations on the set C = {1,2,3,4,5,6}. Prove or disprove the following: If A and B are symmetric, then A U B is symmetric. Homework Equations The Attempt at a Solution The main problem is that I don't know how A U B is defined. In general...
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    Conditional Probability: probability of having a girl.

    It's the probability that it's a girl, given that at least one is a girl - nothing involving a boy. Does that change things?
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    Conditional Probability: probability of having a girl.

    Homework Statement I have two kids. Given that at least one of them is a girl, what is the probability that they are both girls? Homework Equations The Attempt at a Solution I think it's 1/3, because the possibilities are: Boy Boy, Boy Girl, Girl Boy, Girl Girl. There are three...
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    How Do You Write the Electron Configuration for Si and O in SiO4?

    Homework Statement Write the electron configuration for SiO4. Homework Equations The Attempt at a Solution My professor said we just need to show the configuration for Si and O separately. I think Si gains four electrons, so its configuration is 1s2 2s2 2p6 3s2 3p6 But...
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    What is the binding energy in NaCl?

    I know. It's the charges of the ions I'm unclear on. I just wanted to know what the answer would look like if the question was about, say MgO instead of NaCl.
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    What is the binding energy in NaCl?

    Homework Statement Each Na atom transfers 1/6 of an electron, on average, to each Cl atom. Estimate the binidng energy of the ionic bonds in NaCl. Homework Equations The Attempt at a Solution The answer says to use k*q1*q2 / r, where k is the electric constant, q1 and q2 are the...