Transcript DO NOW! - PBworks

Introduction to Metric System
The Metric Scale & System
K
H
D
S
D
C
M
Kilo
Hecto
Deca
Deci
(k)
(h)
(da)
(d)
Centi
Milli
(c)
(m)
grams
meters
liters
BIG
SMALL
EASY WAY TO REMEMBER
King Henry Died Sunday Drinking Chocolate Milk
MASS
The amount of matter that is packed into
an object.
 Use grams to measure mass
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GRAMS
The Symbol g
 Measures non-liquids
 Commonly used in cooking
& food labeling
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What do we use to measure Grams?
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We will use a Triple Beam Balance
How to use a Triple Beam
Balance
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1. Zero the balance
2. Slide all of the riders back to zero
3. Check the pointer (pointing to zero)
4. If necessary, use the adjustment screw to
get back to zero
5. Place the object on the pan and move the
riders along the beams beginning with the
largest mass first
How is mass different than
weight?

WEIGHT: Determined by the pull of
gravity on an object
Note: If you leave Earth…
 Your weight will change
 Your mass will remain constant
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LENGTH
The distance between two points
 Use meters to measure length

METER
The Symbol m
 Measures the
distance between two
points
 Commonly used for
lengths of races

What do we use to measure meters?

We will use rulers
ROUNDING

How long is this line? Round to the
nearest centimeter.
3.0 cm
Nearest 10th of a centimeter
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A centimeter is divided into 10 sections on
a ruler
This value is 1.5 cm
How long is this line

Measure to the nearest 10th of a
centimeter
3.3 cm
VOLUME
The amount of 3-D space an object
occupies
 Use liters to measure volume

Liter
The symbol L
 Measures liquids
 Commonly used for items that
take up space in a container

What do we use to measure Liters?

We will use graduated cylinders and beakers
How to use a graduated
cylinder
MENISCUS: A curve in the surface of a
liquid
 ALWAYS read from the bottom of the
meniscus

How to use a graduated
cylinder
1. Place graduated cylinder on flat
surface
 2. Become eye level with the cylinder
 3. Find the bottom of the meniscus
 4. Record the Volume to the nearest 10th
of a mL

Read the meniscus & record
the volume
Volume of objects
We learned how to find volume of liquids
 Sometimes we want to know how much
space non-liquids take up
 How can we find the volume of non-liquid
objects????
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VOLUME of a REGULAR object
A regular object has even sides
 We can easily use a ruler to measure
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QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
FORMULA

Volume = length x width x height
V=lxwxh
 Units = cm x cm x cm = cm3
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Practice Regular Object #1

Find the volume
Height =
4.0 cm
Width =
3.0 cm
Length = 10.0 cm
Formula:
Substitute:
Answer:
VOLUME of an IRREGULAR
object
An irregular object has un-even sides
 We cannot easily use a ruler
 Use a graduated cylinder
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THE PROCESS
1. Place water in graduated cylinder
 2. Find Meniscus & record the volume
(mL)
 3. Add object to the water
 4. Find the new volume & record (mL)
 5. Subtract (END - START)
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Practice Irregular Object #1
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Find the volume
DENSITY
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How tightly the matter in an object is
packed together
Measuring Density
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Formula: Density = Mass
Volume
Sink or Float
Density of water = 1.0 g/cm3
 Above 1.0 = SINK
 Below 1.0 = FLOAT
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Density of a Regular object
Mass = 60.0 g
 Volume = 120.0 cm3
 Calculate Density:
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Sink or Float?
Density of an Irregular Object
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Mass = 15.0 g
Volume = 5.0 mL
Calculate Density:
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Sink or Float?
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