Determine the heat exchange per m² of area a, between the surface specified below if surface 1 is at 1000 k while surface 2 is at 400 k. all surfaces are black. (i) large parallel planes (ii) long coaxial cylinders of 0.5 m and 1 m dia with inner cylinder hotter. (iii) concentric spheres of 1 m and 2 m dia with inner surface hotter. (iv) parallel planes of 2 m x 2 m size placed symmetrically 1 m apart.

Agas contained within a piston-cylinder assembly e end nation about same energy states, 1 and 2, where pi 10 bar, v undergoes two processes, a and b, between the sam 0.1 m3, ui-400 kj and p2 1 bar, v2 1.0 m2, u2 200 kj: process a: process from 1 to 2 during which the pressure- volume relation is pv constant process b: constant-volume process from state 1 to a pressure of 2 bar, followed by a linear pressure-volume process to +20 0 state 2 kinetic and potential energy effects can be ignored. for each of the processes a and b, (a) sketch the process on p-v coordinates, (b) evaluate the work, in kj, and (c) evaluate process the heat transfer, in kj