Lesson Plan - Get It!
You are helping your mom bake a batch of your favorite cookies. As you read through the recipe, it calls for ½ salt. Not thinking much about it, you dump ½ cup of salt into the cookie batter. When the cookies are baked, you bite into one and realize that the cookies taste extremely salty! What happened? Why are they so salty, and what went wrong with the recipe?
As you learned in the previous Weights and Volume lesson, found under Related Lessons in the right-hand sidebar, you can measure the gravitational force on an object by using a spring scale.
The labels on the scale show the results of this measurement.
In this lesson, you will learn that labels included on any scale are SO important. Similar to labels, it is important to have proper units of measurement to calibrate a scale — to ensure the measurement results are correct. Scales measure weight, and this weight is measured using units such as tons, pounds, ounces, and grams. These units of mass descend in the following order:
1 ton = 2,000 pounds → 1 pound = 16 ounces → 1 ounce = 28.35 grams
In this lesson, you will be calibrating your spring scale into grams.
In the last experiment, you made a spring scale and were not prompted to calibrate, or mark numbers on, your scale. In this lesson, you will be calibrating your spring scale into grams. You NEED to put the proper numbers and labels on your latest measurement tool in order to get accurate results! Join Dr. Z to learn more about how you can calibrate your spring scale!
As you saw in the experiment today, having proper units on your spring scale is very important. You are able to measure weight accurately when you have the correct measurement units and labels to work with on your scale!
Speaking of having proper labels, have you guessed what went wrong when you baked the cookies? When the recipe said ½ salt, it was missing an important label. The recipe should have included the following: ½ teaspoon of salt. Instead, you put ½ cup of salt into the batter! Compare a teaspoon of salt to a cup of salt to learn more about the difference. This is a great example to show why it is so important to have proper labels when working with numbers, especially when calibrating the spring scale!
Continue on to the Got It? section to measure what you've learned so far!