Cold Feet It is January and Sabrina, Kelly and Jill are tired of having cold feet while waiting for the school bus to come in the morning. They decide to design an experiment to test the effectiveness of wool, cotton and nylon as insulators. They fill identical bottles with 200 mL of water at 100oC and place inside each sock. They take the temperature of the water after 20 minutes. Identify the variables::: 1. Independent Variable: 2. Dependent Variable: 3. Identify two constants:

Independent Variable : type of insulator material used

Dependent Variable: temperature of water

Constants: Type of bottle used, volume of water in each bottle

Explanation:

In discussing any experiment, the important factors are; the independent variable(s), dependent variable (s) and constant (s).

In this experiment, the type of insulator material (wool, cotton and nylon) was manipulated and the temperature of water when each insulator is used was carefully measured. The type of bottle and volume of water in each bottle were held constant

The nature of insulator material (independent variable) determined the temperature of the water (dependent variable) when the type of bottle and volume of water in each bottle were held constant.

By comparing the temperature of water when the different insulator materials were used, the best insulator material can be deduced.