Cold Feet

Question

It is January and Haley, Sarah, and Becky 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 100 C and place inside each sock. They take the temperature of the water after 20 minutes.
AMELIE MELG...
Identity the constants that are listed for this experiment. Select all that apply.
teet temperature
amount of water
wool, cotton, and nylon materials
temperature of water
cold days in January

Answer 1

In the described experiment, the constants would be the variables that are kept the same throughout the test to ensure a fair comparison of the effectiveness of the different materials. Based on the options provided, the following are the constants:

1. Amount of water - Each bottle is filled with 200 ml of water, which is kept constant.
2. Temperature of water - The water is initially set to 100 C in each case, which should remain constant at the start.
3. Cold days in January - While this is not a scientific constant in the typical sense, it provides context for the experiment, suggesting that the conditions are similar when the tests are conducted.

The wool, cotton, and nylon materials themselves are the independent variables being tested, not constants. Therefore, the constants identified are:

• Amount of water
• Temperature of water

(Note: "Cold days in January" can be considered a contextual constant, but it may not directly play a role like the other two.)