Author Question: A heat conducting rod, 1.40 m long, is made of an aluminum section that is 0.50 m long and a copper ... (Read 140 times)

Anajune7 · **on:** Jul 29, 2018

A heat conducting rod, 1.40 m long, is made of an aluminum section that is 0.50 m long and a copper section that is 0.90 m long. Both sections have cross-sectional areas of of 0.00040 m2.

The aluminum end and the copper end are maintained at temperatures of 40C and 280C, respectively. The thermal conductivity of aluminum is 205 W/mK of copper is 385 W/mK. The rate at which heat is conducted in the rod is closest to A) 20 W.
B) 18 W.
C) 23 W.
D) 25 W.
E) 28 W.

Question 2

A heat conducting rod, 0.90 m long, is made of an aluminum section that is 0.10 m long, and a copper section that is 0.80 m long. Both sections have cross-sectional areas of 0.00040 m2.

The aluminum end is maintained at a temperature of 40C and the copper end is at 150. The thermal conductivity of aluminum is 205 W/mK and of copper is 385 W/mK. Steady state has been reached, and no heat is lost through the well-insulated sides of the rod. The temperature of the aluminum-copper junction in the rod is closest to A) 61C.
B) 58C.
C) 56C.
D) 54C.
E) 52C.