Multiple Choice
I place a 250-g ice cube (initially at 0°C) in a Styrofoam box with wall thickness 1.0 cm and total surface area 600 cm2.If the air surrounding the box is at 20°C and after 2 hours the ice is completely melted,what is the conductivity of the Styrofoam material? (Lf = 80 cal/g)
A) 9.6 × 10−5
B) 2.8 × 10−6
C) 1.15 × 10−2
D) 2.3 × 10−4
Correct Answer:

Verified
Correct Answer:
Verified
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