Two cylindrical metal rods-one copper, the other lead-are connected in parallel
ID: 2219328 • Letter: T
Question
Two cylindrical metal rods-one copper, the other lead-are connected in parallel with a temperature of 21.0 degree celsius at one end and 112 degree celsius at the other end. Both rods are 0.660m in length, and the lead rod is 2.77cm in diameter a)If the combined rate of heat flow through the two rods is 33.3J/s , what is the diameter of the copper rod?Explanation / Answer
values assumed Ctotal = Q/dT = 33.3/91 w/K Alead = pi*Dlead^2/4 Clead = klead*Alead/L Ccopper = kcopper*Acopper/L Ccopper = Ctotal-Clead kcopper*Acopper/L = Ctotal-(klead*Alead)/L ==> Acopper = L/kcopper*(Ctotal-(klead*Alead/L)) = 0.65/395*(33.3/91-(34.3*pi*0.0276^2 / (4*0.65))) = 5.50217613604823E-4 m^2 Dcopper = sqrt(4Acopper/pi) = 2.64680717818936E-2 m