I have a question relating to waveguides. Fine, but having looked at what TE TM modes are I don't really see how I can find the frequency of the μwave with the information I have. 2. Relevant equations A waveguide with dimensions a & b (short & long sides respetively) propogates in the TM10 mode. What is the frequency of the μwave? Now, I have as a clue "the possible modes for f can be found from the guide dimension & wavelength λ. Where λ= c/f Lovely, but what is the relationsip of f & cross section to λ? 3. The attempt at a solution Surely this is simple enough NOT to have to go into Maxwell's curl equations! I just don't have enough information! Confused, simple!