Transcript Notes – Measurement

Notes –
Measurement
(7th grade)
International System of Units
• a way of measuring based on multiples of ten
(10, 100, 1000…)
• abbreviated S.I.
• also called the metric system
• most of the world uses it
Length
• the distance between two points
• the basic unit: meter
• tool used: ruler or meterstick
NO!
YES!
Length
Length
2.1 2.3 2.5 2.7 2.9
2.0 2.2 2.4 2.6 2.8 3.0
Know what each line represents!
Length
1. Length = ______ _____
Length
2. Length = ______ _____
Length
3. Length = ______ _____
Length
4. Length = ______ _____
Length
1.9
cm
1. Length = ______
_____
Length
4.3
cm
2. Length = ______
_____
Length
16
cm
3. Length = ______
_____
Length
4. Length = ______
5.8
_____
cm
Volume
• the amount of space an object takes up
• the basic unit: depends if it’s solid or liquid
• tool used: depends if it’s solid or liquid
Liquid Volume
• the basic unit: liter
• tool used: graduated cylinder
Liquid Volume
• liquids curve inside
a narrow container
• a meniscus is the
convex or concave
surface of a column
of liquid
How do you measure?
or
Liquid Volume
1.Figure out the scale being used by
interpreting what each unlabeled line is.
7.0 ? 8.0
6.9
6.8
NOPE!
6.7
6.6
6.5
6.4
6.3
6.2
6.1
6.0
Liquid Volume
1.Figure out the scale being used by
interpreting what each unlabeled line is.
YEP!
8.0
7.8
7.6
7.4
7.2
7.0
6.8
6.6
6.4
6.2
6.0
Liquid Volume
2. Line your eye up with the water line.
Liquid Volume
3. Pick the line closest to the bottom of the
curve.
Liquid Volume
or
6.6 mL
Which line?
Volume = ___________
Solid Volume
• the basic unit: cubic meter
• tool used: ruler or meterstick
Solid Volume
• area = length x width
• the unit is squared
meters
meters
6 square meters
6 m2
Solid Volume
• volume = length x width x height
• the unit is cubed
What is the volume?
4 cm x 3 cm x 2 cm
24 cm3
Mass
• the amount of matter in an object
• the basic unit: gram
• tool used: triple beam balance or
electronic balance
Mass
•
Triple-Beam Balance Use:
1. Move sliders until it balances.
2. Add together the numbers on all 3 sliders.
Mass
100 g
60 g
What is the mass? + 7.5 g
167.5 g
Mass
•
To find the mass of ONLY the sand:
1. Find the mass of the empty cup.
2. Find the mass of the sand and the cup.
3. Subtract.
Mass
If the mass of the cup
is 45 g, what is the
mass of only the
sand?
167.5 g
- 45 g
122.5 g
Mass
•
to find the mass of ONLY the sand:
1. Place the EMPTY beaker on the balance.
2. Press the “tare” or “zero” button to get the mass
to zero.
3. Fill the container with what you want to weigh,
and record the mass.
Temperature
• the measure of the average energy
of the motion of particles in a
substance
• the basic unit: º Celsius
• tool used: thermometer
• water freezes at 0ºC and boils at
100ºC.
• put a minus sign (-) if it’s below zero
Temperature
SCALE
each line is
1
__
degree(s)
SCALE
each line is
1
__
degree(s)
SCALE
each line is
2
__
degree(s)
Summarize
Unit
Lab Tool
meter (m)
ruler or
meterstick
Liquid Volume
liter (L)
graduated
cylinder
Solid Volume
cubic meter (m3)
ruler
Mass
gram (g)
triple beam balance
or electronic balance
Temperature
°Celsius (°C)
thermometer
Length