Q$1.$

a$)$ Briefly describe heat generation process citing some practical examples. Why is heat

generation a volumetric phenomenon?

b$)$ A long homogeneous resistance wire of radius $r_o=(5+\frac{n}{1000})mm$ is being used to heat. $($n $=48)$

the air in a room by the passage of electric current. Heat is generated in the wire uniformly

at a rate of $5{10}^7\frac{W}{m^3}$ as a result of resistance heating. If the temperature of the outer

surface of the wire remains at $180C,$ determine the temperature at $r=3\mathrm{.}5mm$ after

steady operation conditions are reached. Take the thermal conductivity of the wire to be

$k=6\frac{W}{m}*K.$

$[10$ points$]$