Recent content by Nexttime35

So, would the distribution of this be N(0,n)?

Actually I believe I know where this comes from. the Sum from i=1 to n of Zi2 = the Sum from i=1 to n of ((Xi-μ)/σ)2 = chi square distribution with n degrees of freedom.

Hi LCKurtz, Thanks for the help. I am wondering where you got this equation from? I know it's the z-score, converting the sample mean into the z-score, but how did you come up with the equation? Thanks.

Well I know that the Sample mean has a normal distribution ~ N(μ,σ2/n), which I think is useful to solve this problem. Now, I am confused about how to use this normal distribution for the sample mean to solve the problem. Any thoughts, using this idea?

Homework Statement Suppose that X has normal distribution. Find the distribution of n(Sample Mean - μ)2/σ2. The Attempt at a Solution I honestly have no idea where to begin with this problem. Any ideas?

OK. I am definitely overthinking this problem. I calculated the heat flow from the bottom layer through to the top layer: Sandstone: -100 mW/m^2 Shale: -78.03 mW/m^2 Sandstone: 74.03 mW/m^2 Thanks for the help!

Put the decimal in the wrong spot. Oops. What about that?

Homework Statement The problem is here: Homework Equations q = heat flow k = thermal conductivity q = -k (dT/dY)The Attempt at a Solution While this is quite an easy question, I just want to verify that I'm doing it correctly. Would it be correct to begin at the bottom of the rock layer...

ΔV is the change in volume. Thus, my logic is that since Vnew equals = (∂x-εxx∂x)(∂y - εyy∂y)(∂z - εzz∂z) = (∂x-εxx∂x)3 (since we are working with a cube, then Dilatation = Vnew-Vo/Vo, plug in for Vnew. However, my text says that if the deformation is so small, then dilatation could...

Yes, if the original volume is 1, and you shrink it by 60%, then the new volume should be 0.4, correct?

I understand that part of the question, and I have read that if the strains are small, then we can assume that exx+eyy+ezz is equal to the dilatation. So if exx=eyy=ezz and exx = 1-(0.6), then would the dilatation be 0.4*3=1.2?

40% of the original volume.

Yes, say it's sand or something. After applying stress to the cube on all sides equally such that those holes are filled, what is the dilatation? Thus, each new side would be (x- 0.6x) for some side x.

Homework Statement Given a cube that is 60% porous, and you subject it to a very large pressure such that the pores close completely, what is the dilatation of the cube? Homework Equations Dilatation (Δ) = ΔV/Vo where Vo is the original volume. Vnew equals = (∂x-εxx∂x)(∂y -...

Homework Statement Given that a rock is 60% porous, and if it's subjected to a large pressure that closes the pore spaces of the rock, what is the dilatation Homework Equations dilatation = ΔV/Vo= εxx + εyy + εzz The Attempt at a Solution Is this problem as easy as it states? If...