| ▲ | pfdietz 4 hours ago | |
The insulation is just more dirt. | ||
| ▲ | cyberax 3 hours ago | parent [-] | |
Homework: compute the heat flux from a 40 meter radius sphere, given the surface temperature 600C and the ambient temperature 0C. Now compute the amount of insulation needed to keep its temperature above 500C for 3 months, given that dry sand has an R value of 0.25 W/mK. | ||