## Introduction

Different types of hot dogs will cool at different rates after they have been cooked. This activity takes the first steps in investigating this phenomenon by measuring the rate that a warmed hot dog cools. Students can compare the ingredients of various types of hot dogs (all-beef, veggie, turkey, etc.) to help explain the differences in cooling rates.

## Objectives

The objectives of this activity are to observe, measure, and explain the capacity of different types of hot dogs to retain heat.

## Summary of the Procedure

Obtain two or three different types of hot dogs. Cut off the ends of the hot dogs, and then measure their mass so that the masses of the hot dogs are the same. Connect your Temperature Probe, start Logger Pro, and use the default settings. Place one hot dog on a paper plate and heat it in a microwave oven for 15 seconds on the highest setting. Insert a Temperature Probe halfway into the hot dog (lengthwise), and start collecting temperature data. Collect data for 3 minutes. Store each trial so that you can plot or analyze all of the data at the end of the experiment. Repeat this process for the other hot dogs.

For best results, make sure that

• The hot dogs are the same mass.
• The hot dogs are heated for the same amount of time.
• The Temperature Probe is inserted into each hot dog identically.
• The temperature data are collected for the same total amount of time.

## Data Analysis

Select a 30 second span of time near the beginning of each data set, and calculate the best-fit line equation. The slope of the line will be considered the rate of cooling for a given hot dog sample. Examine the labels of the packages of the hot dogs. Record the nutrition data for each type of hot dog, paying particular attention to the items that differentiate the products from each other. Students may hypothesize that water content, along with other variations in the ingredients or shape of the hot dog, plays an important role in the rate of cooling.

By Jack Randall