@Anusha would you mind sharing the source?

@PrateekMourya ping me if you want to pick up that question about the beam of nitrogen atoms

Can I send math related questions here?

math room is a bit inactive

Yes, you can ask. Whether you'll get an answer depends on who is around. I'm not especially good at maths so I probably can't answer.

@RishiNandhaVanchi hopefully I can help :-)

I'm solving this matrices problem, first line has given information.

question asks for sum of all elements in A, Im getting -5 but given answer is +5

trying to solve it without getting the rearrangement part involved (we'd get terms like a^2 - bc if we expand the A^2 equation into linear equations)

oh, you said all elements

yes, your A is correct. I am getting the same A.

the sum of the diagonal elements in A^2, is +5, I wonder if thats what the question was asking..

oh

Ill check

thanks!

saturation when all of them have oriented and no more polarization can happen

And note that the BCC lattice has two iron atoms per unit cell.

ok

@JohnRennie But I did not get the correct answer...

Can you explain slightly

What answer did you get, and what is the correct answer?

I got 784.520

Answer is 1500 to 1600

I mean anything in the range is correct

ok

But where did I go wrong then?

Did you take into account that a BCC unit cell contains two iron atoms?

Can you tell me the values @JohnRennie ?

@user586228 Start with a cubic metre of iron, how many unit cells does this contain?

$2/(0.287*10^-9) m^3$

Yes??

This is the total number of atoms

Why should I think about the number of unit cells?

@JohnRennie

We'll call d the cell size i.e. d = 0.287nm, then the volume of the cell is d³. Yes?

Yes

So the number of cells per cubic metre is 1/d³

And each cell contains two atoms, so the number of atoms per cubic metre is 2/d³

OK so far?

Yes...

And each atom has a magnetic moment of 2μ

So the total magnetic moment is 2μ x 2/d³

total magnetic moment per metre cube

Yes?

Yes

Look at the units. They are in metres, so we need to take one cubic metre.

ok

ok

Thanks a lot

:-)

Where did you go wrong? you obviously missed a factor of two somewhere.

Yes I did not do 2/d^3

I straightway did 2 meu /d^3

BCC contains two atoms per unit cell. That's why we have the extra factor of two.

correct..

So basically saturation magnetization is total magnetic moment per m^3?

Yes

ok....

May I have another request@JohnRennie

Yes

Can I discuss a probability problem with you in a separate chatroom

The problem is mainly with solving equations.

@JohnRennie

I'm not particularly good at probability calculations, but you can ask.

ok..

Ca you create a separate chatroom for that?

Can**

@JohnRennie

Let us say you have a question that has many downvotes . So do you remove that question ?. What do you do if it says you cannot remove it as others have invested time in it.

@user102532 are you thinking of this question?

Yes.

@JohnRennie

You can't delete a question if it has an answer, so there isn't anything you can do.

Hmm.but what do you do in that case ?

@JohnRennie

But I've upvoted it so at least it's only -2 now :-)

Oh.Thnx a lot

i just feel bad of it really

@user102532 there isn't anything you can do. If you persuaded ultralegend5385 to delete their answer then you could delete the question, but I would just forget it and move on.

I have some really bad answers from my early days on the site that I cannot delete because they have been accepted. These things we just have to live with.

@JohnRennie :0 unbelievable.

It happens :-)

@JohnRennie thnx. I feel motivated

:-)

@satan29 I'm getting 24 possibilities

right?

@RishiNandhaVanchi prnt.sc/wxydxk