Answer
20 bulbs
Work Step by Step
Calculate the rate of heat flow using equation 14–5. How many 100-watt light bulbs are needed to supply this power and to maintain the temperature difference?
$$\frac{Q}{t}=kA\frac{T_1-T_2}{\mathcal{l}}$$
$$=(\frac{0.84 J}{s \cdot m \cdot C^{\circ}})(16m^2)\frac{30^{\circ}C-(10^{\circ}C)}{0.14m}$$
$$=1920W$$
Round up. Twenty 100-W lightbulbs are needed.
