Suppose you have two black square plates, each at the same temperature, that are placed face to face with a small gap between them. They are both perfectly black and so absorb all electromagnetic radiation incident upon them but suppose one of the plates is emitting twice the radiation of the other. Explain why this would violate the second law of thermodynamics.

Four point charges each having charge q are located at the corners of a square having sides of length a. find symbolic expressions for the following. (a) the total electric potential at the center of the square due to the four charges (use any variable or symbol stated above along with the following as necessary: ke.) vtotal= (b) the work required to bring a fifth charge p from infinity to the center of the square (use any variable or symbol stated above along with the following as necessary: w=