QUESTION 6 (10 POINTS) Calculate the thermal penetration time of the gypsum board (Use gypsum plaster in Table 8.6). TABLE 8.6 Thermophysical Properties of Common Materials MATERIAL THERMAL CONDUCTIVITY DENSITY SPECIFIC HEAT THERMAL INERTIA k(W/M-K) p(kg/m) Cp (J/kg-K) kpcp (Ws/mK?) Copper 387 8940 380 1.30 x 10 Steel 45.8 7850 460 1.65 x 10 Brick 0.69 1600 840 9.27 x 105 Concrete 0.8-1.4 1900-2300 880 2 x 106 Glass 0.76 2700 840 1.72 x 106 Gypsum plaster 0.48 1440 840 5.81 x 105 PPMA 0.19 1190 1420 3.21 x 105 Oak 0.17 800 2380 3.24 x 105 Yellow pine 0.14 640 2850 2.55 X 105 Asbestos 0.15 577 1050 9.09 x 104 Fiberboard 0.041 229 2090 1.96 X 109 Polyurethane foam 0.034 20 1400 9.52 x 102 Air 0.026 1.1 1040 2.97 x 10 Source: Data derived from Drysdale (1999), An Introduction to Fire Dynamics. New York: Wiley. p. 33; and from Table 2.2, Thermal Character. istics of Common Materials found at Fire Scenes, in lcove and DeHaan (2008), Forensic Fire Scene Reconstruction, Second Edition. Upper Sad- Elle River, NJ: Brady/Prentice Hall