Chapter 7, Problem 7.5QAP

Interpretation Introduction

(a)

Interpretation:

The wavelength of maximum emission of a tungsten filament bulb at 2870 K and 3750 K needs to be calculated.

Introduction:

The Wein’s displacement Law states that the maximum wavelength in micrometers for the radiations of the blackbody is represented as follows:

${\Lambda }_{max}T=2.90\times {10}^3$

Here, T is defined as the temperature in Kelvin as it is absolute temperature.

Stefan’s law states that the total quantity of heat energy released per second per unit area by a perfect blackbody is directly proportional/related to the fourth power of the absolute temperature of its surface given by the equation:

E_t = aT⁴

Where a has a value of $5.69\times {10}^{-8}{\text{ Wm}}^{\text{-2}}{\text{K}}^{\text{-4}}$

Interpretation Introduction

(b)

Interpretation:

The total energy output of the bulb in terms of W/m³ needs to be determined.

Concept introduction:

The Wein’s displacement Law states that the maximum wavelength in micrometers for the radiations of the blackbody is represented as follows:

${\Lambda }_{max}T=2.90\times {10}^3$

Here, T is defined as the temperature in Kelvin as it is absolute temperature.

Stefan’s law states that the total quantity of heat energy released per second per unit area by a perfect black body is directly proportional/related to the fourth power of the absolute temperature of its surface given by the equation:

E_t = aT⁴

Where a has a value of $5.69\times {10}^{-8}{\text{ Wm}}^{\text{-2}}{\text{K}}^{\text{-4}}$