For each of these quantities, note the cgs units (or note if it is nondimensional/unitless) and explain what it means and/or in what context it is used: (a) the opacity, k, (b) the optical depth, t, (c) the thomson cross section, ot, (d) the adiabatic index, y, (e) the plasma beta, b, (f) the radiation constant, a, and (g) h.

Asteel tube (k=50 w/mk) of inner and outer diameter di = 20mm and do=26mm, respectively, is used to transfer heat from hot gases flowing over the tube (h-hot = 200w/m2k) to cold water flowing through the tube (h-cold = 8000 w/m2k). what is the cold-side overall heat transfer coefficient uc? to enhance heat transfer 16 straight fins of rectangular profile are installed longitudinally along the outer surface of the tube. the fins are equally spaced around the circumference of the tube, each having a thickness of 2mm and a length of 15mm. what is the corresponding overall heat transfer coefficient uc? *solve for uc in both cases*

Two point charges are separated by a certain distance. how does the strength of the electric field produced by the first charge

Aspring that is stretched 2.6 cm stores a potential energy of 0.053 j. what is the spring constant of this spring?