Recent content by E92M3

Homework Statement An EM wave normally shed on a conductive material (\tilde{\epsilon}=\epsilon+i\epsilon_i,\mu_0). Calculate the phase shift of the electric field of the reflected wave relative to that of the incident wave. Homework Equations...

I know that the metal mesh on the microwave oven door can block microwaves because the holes are much smaller than the wavelengths. It is the same reason why some radio telescopes can be made with a mesh. What is this effect called?

For the 1st one, will u understand if i write: 1 1.(AvB) A 2 2.~A A 1,2 3.B 1,2 vE q.e.d. And the 2nd: 1 1.(H->(I&J)) A 2 2.H A 1,2 3.(I&J) 1,2 ->E 1,2 4.I 3 &E 1 5.(H->I) 2,4...

First let me ask you do u know the format of natural deduction? Do you know the rules of natural deduction?

Ah... I asked the question half a semester ago and now I got it all figured out.

If I have two particles that follows the maxwell velocity distribution: \phi(v_i)dv_i=4 \pi v_i^2 \left ( \frac{m_iv_i}{2\pi kT} \right ) ^{3/2}e^{\frac{-m_iv_i^2}{2kT}}dv_i Why is their combined distribution: \phi(v)dv=4 \pi v^2 \left ( \frac{\mu v}{2\pi kT} \right ) ^{3/2}e^{\frac{-\mu...

Thanks I think I got it now. Just to make sure, so outside the sphere is the same as before because of the uniqueness theorem? I thought it only applies to the potential inside a volume bounded the a boundary where the boundary conditions are defined (inside the sphere). Here, are we treating...

Homework Statement A spherical shell with potential: V(r=R)=V_0cos\theta (a) Please solve the potential inside and outside the shell. (b) if there is a point charge at the center and the potential of the shell keeps the same, solve the potential inside and outside. Homework Equations...

ok, everything is fixed. v stands for or

Sorry the latex is not picking up my "ands" the attached pictures should be more clear.

Homework Statement I am new at logic and I'm stuck on a problem set: a) (~C \vee (A \cap B)) \vdash ((~C \vee A)\cap (~C \vee B)) b) \vdash ((A\cap B) \leftrightarrow (B^A)) c) \vdash (((A \rightarrow B) \rightarrow C) \rightarrow (A \rightarrow (B \rightarrow C))) d) ((A...

Then how can I shorten those wff to make them cleaner?

But what do you mean by "^"? is it &? How can you have (P^Q^R)? I Thought this can't be a wff. Shouldn't it be like ((P^Q)^R) since two two place connective will require two sets of breckets. Also does -Q mean ~Q?

I was given a truth table and I must write a wff with exactly two two-place connective. I am new to logic and don't know where to start. I need to find wff a), b), c) and d). C B A ... wff a) T T T ... T T T F ... F T F T ... T T F F ... F F...

Hi, I'm new to logic. I can fill in a truth table if given a wff but can't do it the other way around. What is the general strategy in finding the wff of a truth table?