Mass
Is how much an object is able to hold or how
much the object contains.
The mass of an object is measured in the unit
grams.
Mass is not the same as Weight!!!
Weight
Is the measure of gravity’s pull on an object.
Weight changes based on the gravity around
you.
For example a person on the Earth would not
weigh the same as they would on the moon.
Here is a video to help you
remember
https://youtu.be/1whMAIGNq7E
The Mass of an object
Can be measured using the Metric System with
the unit grams.
For example mass can be measured in:
Kilograms
Grams
Milligrams
Metric Units
1 Kilogram (kg) = 1000 Grams (g)
1 Hectogram (hg) = 100 Grams (g)
1 Dekagram (dag) = 10 Grams (g)
1 Decigram (dg) = .1 Grams (g)
1 Centigram (cg) = .01 Grams (g)
1 Milligram (mg) = .001 Grams (g)
When Measuring Mass
We use a triple-beam balance to find the mass of
an object.
The objects are placed on the scale and then
you move the weights on the beams until you get
the lines on the right side of the scale to match
up.
Measuring Mass – TripleBeam Balance
1st – Place the object on the scale.
2nd – Slide the large weight to the right until the arm drops below the
line. Move the rider back one groove. Make sure it “locks” into
place
3rd – Repeat this process with the top weight. When the arm moves
below the line, back it up one groove
4th – Slide the small weight on the front beam until the lines match
up.
5th – Add the amounts on each beam to find the total mass to the
nearest tenth of a gram.
Next Class
Our next class will be a lab measuring the mass
of object
Here we will use gram weights and a balance
scale to measure different amounts of grams.
We may also measure objects in our classroom.
Lets Think About Mass?
At this time I would like you to just think about
which unit you would use to measure the mass
of each object.
Would you use a kilogram, dekagram, gram,
decigram, or milligram as a unit to weigh these
following objects?
Unit Facts
Kilogram is a bigger unit.
Objects with more mass are measured in Kilogram.
Examples – cycle, car, telephone
Objects with less mass are measured in grams.
Example – pins, pencils
A paperclip
What unit would you use to
measure a paper clip?
A Gram
Bag of Rice
What unit would
you use to
measure a bag of
rice?
A Kilogram
A Snowflake
What unit would you
use to measure a
snowflake?
A Milligram
2 Nickels
What unit would
you use to
measure 2 nickels
A Dekagram
Bananas
What unit of
measurement (grams or
kilograms) would be best
to measure the weight of
a bunch of bananas?
Kilograms
A feather
What unit of
measurement
(grams or kilograms)
would be best to
measure the weight
of a feather?
Grams
Bag of flour
What unit of measurement
(grams or kilograms)
would be best to measure
the weight of a bag of
flour?
Kilograms
A Seashell
What unit of
measurement
(grams or kilograms)
would be best to
measure the weight
of a small seashell?
Grams
GREAT JOB!!!
More or less
Here you will be given two units you will have to
tell me if the first unit is more or less then the
second unit.
Do the work at your seat quietly.
Raise your hand when you are finished.
Which is…..
Which weight is lighter?: 60 grams or 3 kilograms?
60 grams is lighter!
Which weight is heavier: 1,000 grams or 1 kilogram?
Trick question – they’re the same weight!
Which weight is lighter: 700 grams or 1 kilogram?
700 grams is lighter!
Is 960 grams more or
less than a kilogram?
Answer- 960 grams is less than a Kilogram as 1 Kg
= 1,000 grams
960 grams < 1,000 grams
Converting Using Grams
Here you will convert one amount from one unit
to another.
Do the work at your seat quietly.
Raise your hand when you are finished.
How many grams are
there in 9 Kg?
Answer- 9,000 grams
A Kitten has a mass of
3,000 grams. What is
its mass in Kilograms?
Answer – 3 Kg
Review
Kilogram is used to
measure ----.
a) Length
b) Capacity
c) mass
Which has more mass?
A
B
C
True or False
a) 5 Kg is less than 3299 grams
a) Mass of an object does not depend
on the size of an object
Grams and Kilograms are Metric units to
measure weight.
Most countries in the world (countries in green)
use Metric units like grams and kilograms to
weigh things.
Now Try this worksheet
This should be completed alone and in silence.
if you do not finish please take it home and
complete it for homework.
We will go over the worksheet in the next class.