Measurement

Everything we do and everything we interact with is associated with some sort of measurement. Measurement is a way of describing something using a common basis. Understanding a few of the different types of measurement is invaluable for being able to describe things and for all sorts of different professions in the world from being a teacher to being a fisherman to being an engineer or a ballerina.

Experiment Title:

Length, Weight, Temperature or Volume?

Objective:

The objective of this lab is to learn about some of the most common measurement types and the most common measurements within those types. Once we learn about the different measurement types we are going to do a lab in which we attempt to figure out what type of measurement we are looking at in several different problems.

Background on Measurement:

Every day you deal with measurements all around you without even thinking about it. Think about when you mom tells you to put a coat on because it is cold outside, this is a form of measurement that is based on the variation from a comfortable temperature for people. This measurement is imprecise, meaning that you mom in this example is not telling you it is 30 degrees Fahrenheit outside (which is a precise measurement). 

Since our first example dealt with temperature let’s start with explaining temperature. Temperature is a measurement of the excitement of an atom, the more an atom moves the warmer it is. There are three main temperature scales:    Kelvin, Celsius, and Fahrenheit. Kelvin is the most expansive scale in that absolute zero in Kelvin is the point at which atoms from a gas do not move and are essentially frozen. If you think about going into space where you do not have the warm and inviting atmosphere of the Earth surrounding you the average temperature there is 2.7 degrees kelvin (-270.7 degrees Celsius or -455 degrees Fahrenheit, that is super-duper cold). Let’s use a more common example, think about water, when it is warm outside water is liquid (it sloshes around and you can splash in it), when it is cold outside it is a solid (it is hard and slippery enough to go ice skating), and when your parents boil water on the stove it becomes a gas (moving all around and filling up any container it is put in and can be rather hot to touch). With this example we are not saying the exact temperatures of the water but know that it is changing in temperature when it is ice it feels very cold to the touch, when it is water it can feel cold to neutral to hot and when it is gas it can feel hot (water can also affect how we feel air temperature because it creates humidity but that is a topic for another lab). This is an imprecise way of looking at the temperature of something. To look at it more precisely some super smart people came up with thermometers which would show changes with temperature changes. We now use thermometers to check body temperature, inside temperature and outside temperature, to name a few, and those thermometers use different scales. The Fahrenheit scale sets the freezing point of water at 32 degrees, while the Celsius scale sets the freezing point of water at 0 degrees.

Now that we know a bit about temperature let’s look at another measurement type length. Length has to do with the distance of something. Think about how tall you are, that measurement is a length, it is the distance from the bottom of your feet to the top of your head. For measuring distance the two main scales that are used are Metric and English. The metric system is in common use throughout the world and is a standard in most scientific fields. This system uses centimeters, meters and kilometers as their common units for length. One centimeter is 1/100 of a meter and 1 meter is 1/1000 of a kilometer. The English system (or the United States Customary Units, as it is currently referred to in the US) is the system that many of us in the United States have grown up with. This system uses inches, feet, and miles as our common units of length. One inch is 1/12 of a foot and one foot is 1/5280 of a mile. These seem like odd measurements when you compare them to metric which is based on 10s, but has been in common use for hundreds of years. Since you do need to be able to use either scale and convert between them simple proportions have been created, for instance 1 inch is equal to 2.54 cm. Now I could go on and on about converting between units, but for now we will leave it at that and in another lab with do some amazing stoichiometry (then you can really test your parent’s knowledge of the different measurement systems).

Length is an awesome measurement when you are talking about a two-dimensional object or idea, but what if you want to know the overall size of something? You could measure the length, then the depth, and then the width and have an idea, but we could go one step further and multiply the values together and create a new measurement called volume, this measurement represents the three-dimensional space that an object takes up. Volume is a great measurement for liquids where it is very hard to determine a length since a liquid will conform to any shape that the container holding it is. As with length there is the metric system and the English system. For metric common volume measurements are milliliters (cm x cm x cm = mL) and liters. For English units teaspoons (1 teaspoon is equal to 5 mL), cups and gallons are common measurements.

Weight or mass is another unit that has two common systems of measurement. In common usage, the mass of an object is often referred to as its weight, though these are in fact different concepts and quantities. Weight deals with the mass of an object multiplied by the force of gravity that is exerted on it, whereas mass refers to the amount of matter that makes up an object. For what we are doing in STEM club we will not make a distinction between mass and weight in this lab (it will be important in our Physics and Chemistry labs but will be covered more in those). In terms of units, metric units for mass are commonly grams and kilograms. For English units weight is commonly ounces and pounds (2.2 pounds equals 1 kilogram). Weight/mass is important for knowing how heavy an object is and how much force it will exert on another object when tossed or dropped, think about it in terms of a ball. If I throw a beach ball (which is very light) as hard as I can at my friend it would potentially hit them and not really hurt, now if I throw a ball filled with sand at my friend just as hard and it hits them they would get hurt and cry (let’s not try this as we do not want anyone hurt). The idea is that even though the balls are the same size and shape the amount that they weight is different and the more weight the harder that ball will hit my friend.

The last type of measurement we are going to talk about today is time (there are plenty of other types of measurement and common types that combine some of the types of measurement above but for now knowing these 5 types will give us a great start on our science journey, if you want to learn about more types after this lab look at the extension activities). Time is a concept that fascinates all of us at one point in our lives. We as a species live in linear time, that means we move in one direction we are born, we grow up, we have careers and we retire, all in a set order that we cannot change. We are aware of time by the changes in the day, day goes to night then becomes day again, and the changes in the seasons, summer goes to fall then to winter then to spring and back to summer. To keep track of the movement of time different scales have been created, some calendars and time scales are based on the cycles of the moon, some are based on the movement of the earth around the sun, and some are based on the revolution of the earth and its movement around the sun. There are standard units of time used consistently through the whole planet: the second, minute, hour, day, and larger units of time. One second is 1/60 of a minute, one minute is 1/60 of an hour, and one hour is 1/24 of a day. By standardizing the time throughout the globe travel between countries was greatly simplified and people could figure out what time it would be in a place like Norway when they are in Seattle.

Now that we know five of the basic measurement types and several of the units that go along with them we can now move on to doing our fun experiment for the day. We have received a letter from Agent Q asking for help on figuring out a secret message, this message is hidden in questions relating to the different types of measurement that we learned about today (how awesome is it that these things lined up!). So let’s see if we can help him and make sure we understand what we learned so far.

Materials

• Pencil
• Secret Message problem set
•  Lab notebook

Method

Prepare Experiment

1.      write in your lab notebook the setup for your experiment

2.      on 10 different lines write the numbers 1 – 10 so that you can write each answer to the questions and the word that is associated with that answer

Run Experiment

1.      Go through and answer each question recording your answers in your lab notebook

2.      After you have your answers written down write out the phrase that you get from your answers, does it make sense, if not go back and re-answer the questions that do not make any sense.

Analyze Data

1.      There is not a lot of data from this lab but we will go through and discuss together why each answer is that type of measurement when we are come back together.

Conclusions

Measurement is key for science and most everything we do in day to day life. Knowing how to count means we can exchange money for goods or figure out who scores more goals in a soccer game. Knowing how to determine lengths means we can see how much we grow each year or figure out far away grandma lives (and consequently where the good candy is). Knowing how to determine volume means we can get out a glass of water without wasting extra or know how full to make the bathtub so that water does not go over the side and make steam come from mom’s ears. Knowing how to tell time we can figure out how long until the next STEM club or how much more you running around than the day before. Knowing the temperature we can know when water it too hot to touch and could burn us or know when it is too cold outside to not wear a coat. Knowing the weight or mass of something we can know if something is too heavy for us to safely lift or how strong we are getting from lifting our baby brother or sister each day. By understanding the basic units that go along with these common measurement systems we open up so many possibilities in science and can do anything we set our minds to.

Make It Your Own

Go home and look at everything in the pantry and see if you can figure out how something is measured or should be measured, one thing to consider is something like flour, in England a lot of baking is done by using an exact mass not a volume of a material, but in the United States baking is done more by using volume. Do you think you can figure out how you would determine the mass of flour that is needed for one cup of flour here? If your parents have a kitchen scale you may be able to even test your idea (with their permission of course).

Extension Activities to do at home

See if you can test your parents, come up with your own measurement questions that give them a very nice secret message, like “You are Amazing!” “Thank you for all you do” “I promise to actually listen to you”. If you need help coming up with it have one parent help you and then have another actually try to figure it out or test your siblings or babysitter.