Chapter 14, Problem 41P

To determine

The temperature difference across inner and outer surface of glass

Answer to Problem 41P

Solution:

5°C

Explanation of Solution

Given Info:

100W bulb generates 95W heat. Radius of the bulb is 3 cm and thickness 0.5 mm.

Formula used:

Rate of heat flow can be calculated by

$\frac{Q}{t}=kA\frac{T_1-T_2}{l}$

Calculation:

$\frac{Q}{t}=kA\frac{T_1-T_2}{l}$

Substituting the values

$\begin{array}{l}95\text{W}=\frac{0.84J}{s.m.°C}(4\pi {(}^{0.03})\frac{\Delta T}{0.00050m}\\ \Delta T=5\text{°C}\text{.}\end{array}$