Consider laminar, parallel flow past an isothermal flat plate of length L, providing an average heat transfer coefficient of hL. If the plate is divided into N smaller plates, each of length L L N = /N, determine an expression for the ratio of the heat transfer coefficient averaged over the N plates to the heat transfer coefficient averaged over the single plate, h h/ L N, , L 1.

Describe one experiment in which the glass transition temperature and melting temperature of a totally amorphous thermoplastic material can be determined. show the relevant experimental results in a diagram which should be properly annotated with the two temperatures clearly marked. what is likely to happen to the curve in the diagram if the amorphous polymer is replaced by a thermosetting type?