Question: What is the thermal conductivity of a material if a 1 m² area of it conducts 100 J of heat in 10 seconds with a temperature difference of 20°C?
Options:
Correct Answer: 5 W/m°C
Solution:
Using the formula Q = kA(T1-T2)t, we find k = Q / (A(T1-T2)t) = 100 J / (1 m² * 20°C * 10 s) = 0.5 W/m°C.