Recent content by agentnerdo

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    Understanding the Derivative of F=Fi (sin ct)

    Homework Statement differentiate F=Fi (sin ct) The Attempt at a Solution Fi is a constant = Fi (-cos ct)(c) That is the solution I keep getting, but my buddy keeps getting Fi (- cost ct)/c in other words, he thinks - cost ct should be divided by c, anyone care to...
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    Deriviate proof d/dt[r (v a)]= r(v a)

    that was an epic fail on trying to use brackets... derivative of [r (v times a)] = r ( v times a*) a* is the derivative of a. question asks to prove that both sides are equal.
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    Deriviate proof d/dt[r (v a)]= r(v a)

    Hey guys, I really do not even know how to get this question started. Homework Statement \frac{d}{dt}[r (v x a)] = r (v x a) the last a is supposed to have a period on top as such it is \frac{d}{dt}[r (v x a)] = r (v x \frac{d}{dt}a) d, v, and a are position, velocity, and...
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    Calculate Expectation Value & SD of N1, N2 in 0.1m^3 Vacuum Chambers

    The conc.of molecules in two ultra-high-vacuum chambers of volumes V1=V2=0.1m^3 is 10^6 molecules/m3 You count the # of molecules N1 and N2, in each chamber at some moment of time. a.find the expectation value and the SD of N1 and N2 . calc \sigma_{N1}, sketch the prob distribution of N1...
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    Advanced vector question incl. parallelepiped

    I think I am kind of getting it. Most examples online use three numbers (ie =3i, 5j, 6k) As such you get a nice little box In this case, we are missing, for B= any j value, does this mean we assume j=1 for b? this is what I have so far i j k 2 1 1 (I...
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    Solving Dimensional Analysis: Find V in Terms of P & Density

    I think I got it! Pressure= F/A [M^x][L^-1x][T-^2x] Density= [M^y][L^-3y] For M M^y plus M^x= 0 For T -1 = -2x x= 1/2 For L 1= -1x - 3y sub in x=1/2 x= 1/2 As such, Velocity = sqt (pressure/density) I hope this it? yes? I did not...
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    Advanced vector question incl. parallelepiped

    Homework Statement Given the three vectors A = 2i + j, and B= i + k, C=4j, find the following a) |A X B| b) |A x (B X C)| c) the volume of the parallelepiped whos concurrent edges rae represented by A B C. The Attempt at a Solution I am stuck on A. I assume it couldn't...
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    Converting speeds and time?

    You did not really state where your stuck...which it makes it a bit hard to help you. But here is a try for the first q "Convert the following times. All units must be shown as well as cancellations. f) 0.35 minutes to years" This is a dimensional analysis type q. Used commonly in...
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    Solving Dimensional Analysis: Find V in Terms of P & Density

    I think I have a bit of a hang on this now... [L][T^-1] = [M][L^-1][T-^2] [M][L^-3] We ignore [M] as it is not on the left side thus; [L][T^-1] = [L^-1x][T-^2x] [L^-3x] -1 = -2x -------> x=1/2 1= -1x - 3y sub x= 1/2 y= -2/3 V= sqt pressure / density ^2/3...
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    Solving Dimensional Analysis: Find V in Terms of P & Density

    Hey lwando, V= [L^3] Pressure= F/A [M][L^-1][T-^2] Density= [M][L^-3]
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    Solving Dimensional Analysis: Find V in Terms of P & Density

    Homework Statement The speed v of sound waves in air depends on the atmospheric presure P and density. By using the method of dimensional analysis, find an expression for v in terms of P and density. Homework Equations What I have so far; V= density x P I found a textbook...
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