Measurement of Liquids (the volume of an object, or “How much space does it take up?)
If a student asks his teacher how much water is in the class aquarium, he is asking a question about volume.
Volume is the amount of space that an object takes up.
Since volume is a liquid measurement, it is measured in milliliters (m - mini) or liters (l – larger).
To find the capacity/volume of the items below, you would use the following measurements:
Milliliters
Medicine dropper
Liters
2-Liter bottle of soda
(To get an idea of a liter, imagine half of this!)
A bucket
An aquarium (fish tank)
An automobile’s gasoline tank
A bathtub
Many scientists use graduated cylinders to conduct experiments and measure liquids.
Remember, to measure volume/capacity (the amount of space an item takes up), use L or ml.
Using the picture of the graduate cylinders below, fill in the correct number of ml that is already in the
graduated cylinder, and the amount that will be present once the specified amount of liquid is added.
____ + 5 ml = ______
____ + 11 ml = ____
____ + 9 ml = ____
Measurement of Mass (the weight of an object, or “How much does it weigh?”)
There are several tools used to measure mass or the weight of an object. Most of these tools are related to a
type of balance scale. Weights [usually in the form of grams (g) or kilograms (kg)] are placed on one side of
the scale, while the object is placed on the other side of the scale. When enough weights are added to cause the
two to be equal in weight, you may add up the number of grams in order to determine the weight of the object.
Balance scales (used to measure mass) can come in different shapes and sizes:
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Balance-scale
Double Pan Balance
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Triple Beam Balance
Balance Scale
Remember, to determine the mass/weight of an object, you only need to add up the grams!
Using this illustration, what would the most accurate reading of
the mass of this rock be? (Don’t forget to write “g” for grams!)
__________
How many grams are shown in this picture? (Don’t forget to write
“g” for grams!
__________
Can you measure the mass of a marble with a Triple Beam Balance?
QuickTime™ and a
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YES! You can measure the mass of a marble with a Triple Beam Balance!
You can measure the mass (weight) of many items with a Balance. Charts
are often used in science to record information. Once the information has
been recorded, you may then interpret the information in the charts
(analyze). Many answers may be obtained by interpreting charts. Use the
illustration to answer the following question:
The majority of fifth grade students have backpacks with a mass of
_____kg.
Notice that we used kilograms to provide the measurement of mass for the backpacks. Grams are very small and
are usually used for lightweight items.
If we wanted to measure the size and mass of this block, we would use a ruler
and a balance.
Ruler - measures size or length
Balance – measures mass or weight
Measurement of Length (the size of an object, or “How long is it?”)
Any form of measurement that has the word, “meters” in it, is referring to its length.
This includes: millimeter, centimeter, meter, and kilometer!
Notice that it takes about 2.5 cm (centimeters) to equal 1 in. (inch).
There are 10 mm (millimeters) in 1 cm (centimeter)!
There are 100 cm in 1 m (meter) or about 3 ft. (feet)!
1 km is almost equal to 1 mile!
When an item is as small as a couple of your fingernails, you will want to use millimeters.
When an item is as wide/long as your hand, but smaller than a doorway, you will want to use centimeters.
When an item is longer/higher than a doorway, you are going to want to use meters! (ex. school hallway)
When an item is as long as the New York is from your house, you will want to use kilometers!
Look at the comparison chart below to see what unit of measurement would be used:
Millimeters
Centimeters
the
a moth’s wingspan
(8 mm)
Meters
length of a tadpole
(3.1 cm)
the width of a student’s hand
the distance on a road
the length of an adult human
footprint is 20 centimeters.
the growth of a leaf
the height of a tree
To find out the
growth of the leaf
in this chart, do
some simple math!
12.5 cm (June 30)
- 7.5 cm (June 1)
5.5 cm total leaf growth or simply
round to 6 cm!
Measurement of Time (How much time passes before...? What is the speed of...? How long until...?)
The measurement of time can help determine many things. Scientists will most often record
time in seconds, and parts of a second (decimals).
To find out how long a rubber ball bounces before it comes to a stop, you would want to
record the number of seconds that the ball is bouncing/moving.
When you want to show how much something has changed over a period of time, you will usually use a line
graph. For example, if you want to show how much the use of gasoline has increased over the last ten years, you
could display it on a line graph.
Measurement of Temperature (How hot is it? How cold is it?)
What temperature does this thermometer show? 22 Celsius
When using a thermometer, the best unit to measure temperature is degrees Celsius.
The temperature of the object being measured causes the liquid in a thermometer to move.
The Scientific Method
Observation
An observation is only something that you can see with your eyes at that moment!
Variables
Manipulated Variable -
This is the variable that “man” changes in the experiment to achieve various
results. This variable is also called the Independent Variable.
Responding Variable - This is the variable that provides results because someone has manipulated the other
variable! This variable is NOT changed by the experimenter! Since this variable is
dependent upon the other one....it is also called the Dependent Variable.
Look at the pictures of the experiment to the left. Then, look at the choices below.
Circle the manipulated variable. Now, put a box around the responding variable.
a. The volume of water evaporated
c. The position of the light bulb
b. The position of the thermometer
d. The amount of water at the
start of the experiment.
Circle the responding variable. Now, put a box around the manipulated
variable (the variable NOT being held constant).
a. The amount of heat
c. The speed in which the water
boils
b. The amount of water
d. The amount of salt
Circle the variable that changes in this experiment.
a. The shape of the object
c. The shape of the ramp
b. The length of the ramp
d. The height of the box
Which variable was manipulated in the illustration to the
left?
___________
of the ______________
In an experiment it is important to control your variable to be sure your experiment is fair.
In order for an experiment to be “fair,” only ONE variable must be changed at a time!
List the variables that are different in this experiment:
fresh water
salt water
1/3 cup of water
3/4 cup of water
Since there is more than one variable that changes,
this would NOT be a “fair” and accurate experiment.
The following questions and examples relate to the fairness of an experiment. Carefully look for the correct
answer.
To find out which soil absorbs (holds) moisture best, each container shown must – (Circle one)
a. be made of a different material
c.
be tested by the same person
b. have soil from the same place
d.
contain the same amount of
soil
Since the experiment is designed to test the soil, it is only fair if each type of soil is the same amount as the
others!
If you wanted to make sure the experiment below is fair, you would want to compare all of the elements to
make sure there is only one variable being changed. In the table below, write “Same” or “Different” beside
each element (variable) of the experiment.
Type of water
Size of the glass
Amount of water
Since there is only one difference (variable),
this would be a fair experiment.
Height of flame OR the
distance of the glass from
the flame
In an experiment it is important to control your variable to be sure your experiment is fair.
In order for an experiment to be “fair,” only ONE variable must be changed at a time!
To list the variables in this illustration, look for the things that are
different between the two items and list them:
Type of water
Amount of water
Different
Different
Since there is more than one variable that changes, this would NOT be a “fair” and accurate
experiment.