Question

The block in the drawing has dimensions L0×2L0×3L0,where L0 =0.2 m. The block has a thermal conductivity of 150 J/(s·m·C˚). In drawings A, B, and C, heat is conducted through the block in three different directions; in each case the temperature of the warmer surface is 35 ˚C and that of the cooler surface is 16 ˚C Determine the heat that flows in 6 s for each case.

Answer 1

1140 J, 6840 J, 10260 J

Step-by-step explanation:

Lo x 2 Lo x 3 Lo, Lo = 0.2 m, K = 150 J/(s · m · C˚) , T = 35 ˚C, T' = 16 ˚C,

time, t = 6 s

The heat conducted is

`H = (K A (T - T') t)/(d)\\\\H = (150* 3* 0.2* 0.2* (35-16) * 6)/(3* 0.2)\\\\H = 1140 J`

The heat conducted is

`H = (K A (T - T') t)/(d)\\\\H = (150* 3* 0.2* 2*0.2* (35-16) * 6)/(3* 0.2)\\\\H = 6840 J`

The heat conducted is

`H = (K A (T - T') t)/(d)\\\\H = (150* 3* 0.2* 2*0.2* (35-16) * 6)/(2* 0.2)\\\\H = 10260 J`