A Heat Conducting Rod, 1 $0.70 \mathrm {~m}$ Long Both Sections Have a Cross-Sectional Area Of Wrapped

Multiple Choice

A heat conducting rod, 1.60 m long and wrapped in insulation, is made of an aluminum section that is 0.90 m long and a copper section that is $0.70 \mathrm {~m}$ long. Both sections have a cross-sectional area of $0.00040 \mathrm {~m} ^ { 2 }$ The aluminum end and the copper end are maintained at temperatures of $30 ^ { \circ } \mathrm { C }$ and $170 ^ { \circ } \mathrm { C }$ respectively. The thermal conductivities of aluminum and copper are 205 W/m ? K (aluminum) and 385 W/m ? K (copper) . At what rate is heat conducted in the rod under steady state conditions?

A) 9.0 W
B) 7.9 W
C) 10 W
D) 11 W
E) 12 W