Chapter 9, Problem 33E

Interpretation Introduction

Interpretation:

The kilowatt-hour of energy contained in Chocolate chip cookie (having 200 kcal and the duration for which a 100 W bulb can light up using that energy, are to be calculated

Concept introduction:

Unit conversion is defined as the process in which multiple steps are present and is used to convert the unit of measurement for the same given quantity. It is determined by multiplication with a conversion factor.

The fraction in which numerator and denominator are the same quantities but are determined in different units is known as a conversion factor.

The power generated by utilizing chemical or physical resources for providing heat and light or for carrying out various processes, is known as energy. The SI unit of energy is joule.

Since, 1 Kcal is equal to 1000 cal, hence, conversion factor is as follows:

$\frac{1\text{ Kcal}}{1000\text{ cal}}$

Since, $1\text{ gram calorie}=4.18\text{ joule}$, hence conversion factor is as follows:

$\frac{4.18\text{ J}}{1\text{ cal}}$

Since, $1\text{ Kilowatt hour}=3.6\times {10}^6\text{ joule}$, hence, conversion factor is as follows:

$\frac{\text{3}\text{.6}\times {\text{10}}^6\text{ J}}{1\text{ kWh}}$

Since, $1\text{ quads}=\text{1}\text{.6}\times {\text{10}}^{18}\text{ joule}$, hence, conversion factor is as follows:

$\frac{\text{1}\text{.6}\times {\text{10}}^{18}\text{ J}}{1\text{ quad}}$