Measurements (use metric system) Measuring be precise/accurate reliable/standardized understood by audience

Measurements

(use metric system)

Measuring

be precise/accurate

reliable/standardized

understood by audience

The Metric System (required in this class with a few exceptions) --Why use the metric system? M ost of the world and scientists use SI system Metrics based on units of 10 (easy to convert) Kilo=1000 Hecto=100 Deka=10 **(meter, liter, etc) deci=.1 centi=.01 milli=.001

--Why use the metric system?

M ost of the world and scientists use SI system

Metrics based on units of 10 (easy to convert)

Kilo=1000

Hecto=100

Deka=10

**(meter, liter, etc)

deci=.1

centi=.01

milli=.001

Length base unit=meter (approximately floor to hip) cm=width of pinky km=12 city blocks Instruments: tape measure, ruler, meter stick How long is this shell (cm/mm)?

Length

base unit=meter (approximately floor to hip)

cm=width of pinky

km=12 city blocks

Instruments: tape measure, ruler, meter stick

Liquid Volume (amount of space object takes up) base unit= liter instrument=graduated cylinder (eye level)- note: read bottom of meniscus Which has more volume? 2 liters Pepsi or 2 liters of air How much liquid is in this graduated cylinder?

Liquid Volume (amount of space object takes up)

base unit= liter

instrument=graduated cylinder (eye level)- note: read bottom of meniscus

Which has more volume?

2 liters Pepsi or

2 liters of air

Solid Volume (“size” of object) cubic meter use ruler and formula (if regular shape) example: rectangle/square is L x W x H use displacement (if irregular shape) note: 1cc = 1 mL (so 5ml=5cc) 1 mL=1/5 teaspoon Be sure all instruments START on zero****

Solid Volume (“size” of object)

cubic meter

use ruler and formula (if regular shape)

example:

rectangle/square is L x W x H

use displacement (if irregular shape)

note: 1cc = 1 mL (so 5ml=5cc)

1 mL=1/5 teaspoon

Mass (amount of matter in object) gram (approximately a paper clip) Family car= 1,000 kg Instrument: balance be sure to start on zero!! does not change with gravity

Mass (amount of matter in object)

gram (approximately a paper clip)

Family car= 1,000 kg

Instrument: balance

be sure to start on zero!!

does not change with gravity

Weight Measure of gravitational attraction you can be “weightless” you weigh less on moon (same mass) metric unit= Newton (an apple) instrument=spring scale weight= mass x 9.8 (for Earth) ex: 90 kg person weighs 822 N

Measure of gravitational attraction

you can be “weightless”

you weigh less on moon (same mass)

metric unit= Newton (an apple)

instrument=spring scale

weight= mass x 9.8 (for Earth)

ex: 90 kg person weighs 822 N

Celsius 100º=boiling of pure water at sea level 0º=freezing room temperature about 20-25ºC thermometer some scientists use Kelvin add 273 to Celsius 0 K=absolute zero (motion stops)--theoretical Temperature

Celsius

100º=boiling of pure water at sea level

0º=freezing

room temperature about 20-25ºC

thermometer

some scientists use Kelvin

add 273 to Celsius

0 K=absolute zero (motion stops)--theoretical

Remember Mass Beam Balance grams Weight Spring Scale Newtons Temperature thermometer Deg. Celsius Length centimeters ruler Liq Volume grad cylinder mL Solid Volume grad cylinder if irregular ruler/formula if perfect shape cubic cm Area = LxW (use ruler) units = cm 2

Mass Beam Balance grams

Weight Spring Scale Newtons

Temperature thermometer Deg. Celsius

Length centimeters ruler

Liq Volume grad cylinder mL

Solid Volume grad cylinder if irregular

ruler/formula if perfect shape cubic cm

Area = LxW (use ruler) units = cm 2

Density Mass Volume units: g/mL or g/cc If greater than 1, object will sink in water If less than 1, object will float in water Ex: 2.7 g/cc would ___________ in water. use balance graduated cylinder (or ruler) (calculator)

Mass Volume

units: g/mL or g/cc

If greater than 1, object will sink in water

If less than 1, object will float in water

Ex: 2.7 g/cc would ___________ in water.

use

balance

graduated cylinder (or ruler)

(calculator)

Examples Substance Density (g/cc) GOLD 19.3 LEAD 11.3 ALUMINUM 2.7 SEAWATER 1.025 PURE WATER 1.00 ICE 0.92 GASOLINE 0.7 OAK 0.7 OXYGEN 0.0014 HELIUM 0.0002

Substance Density (g/cc)

GOLD 19.3

LEAD 11.3

ALUMINUM 2.7

SEAWATER 1.025

PURE WATER 1.00

ICE 0.92

GASOLINE 0.7

OAK 0.7

OXYGEN 0.0014

HELIUM 0.0002

TRY THIS… A square block of rock salt has a mass of 10.7 grams. Each edge of the block has a length of 5.0 cm. What is the density of the rock salt? (include correct units) .0856 g/cc

A square block of rock salt has a mass of 10.7 grams. Each edge of the block has a length of 5.0 cm. What is the density of the rock salt? (include correct units)

.0856 g/cc

Practice measuring density Density of “rock”—in your groups … What if you have half the amount of rock? TRY THIS: Assume you are in a 25 ° C room with rock that has a density of 8 g/cc. This rock glows and weighs 10 Newtons. After you carefully observe its yellow glow, you determine its mass to be 16 grams. What is the rock’s volume (include proper units)? … .. 2 cm 3

Density of “rock”—in your groups

… What if you have half the amount of rock?

TRY THIS:

Assume you are in a 25 ° C room with rock that has a density of 8 g/cc. This rock glows and weighs 10 Newtons. After you carefully observe its yellow glow, you determine its mass to be 16 grams. What is the rock’s volume (include proper units)?

… .. 2 cm 3

More practice with density Density lab (liquids) Density blocks Coke vs Diet Coke

Density lab (liquids)

Density blocks

Coke vs Diet Coke

..as time permits Converting SI unit move decimal place left or right (you are multiplying or dividing by multiples of 10) like converting between dollars and dimes Remember King Henry

..as time permits

Converting SI unit

move decimal place left or right (you are multiplying or dividing by multiples of 10)

like converting between dollars and dimes

King KILO 1000 Henry HECTO 100 Died DEKA 10 Monday (m, L, g) 1 Drinking deci 1/10 (.1) Chocolate centi 1/100 (.01) Milk milli 1/1000 (.001)

King KILO 1000

Henry HECTO 100

Died DEKA 10

Monday (m, L, g) 1

Drinking deci 1/10 (.1)

Chocolate centi 1/100 (.01)

Milk milli 1/1000 (.001)

Let’s try these TOGETHER… 600 millimeters = ? meters 0.35 liters = ? milliliters 1,050 grams = ? centigrams

600 millimeters = ? meters

0.35 liters = ? milliliters

1,050 grams = ? centigrams

Examples: 3.2 meters = ________ cm 320 3 mm = _____________dm .03 4.72 g = ______________kg .00472

3.2 meters = ________ cm

320

3 mm = _____________dm

.03

4.72 g = ______________kg

.00472

If you want to measure the length and width of your classroom, which SI units would you use? Which unit would you use to measure the amount of matter in your textbook? Which would you use to measure how much water a drinking glass holds? When would you use the Celsius scale? What is the smallest units on the metric ruler? How many mm are there in 1 cm? 1,000 meters = ________km

If you want to measure the length and width of your classroom, which SI units would you use?

Which unit would you use to measure the amount of matter in your textbook?

Which would you use to measure how much water a drinking glass holds?

When would you use the Celsius scale?

What is the smallest units on the metric ruler?

How many mm are there in 1 cm?

1,000 meters = ________km

Metric Review Inspiration presentation

Inspiration presentation

What instrument and unit would you use to measure the following? the volume of a can of gasoline the length of your foot the mass of a vitamin tablet the density of a cube of wood

the volume of a can of gasoline

the length of your foot

the mass of a vitamin tablet

the density of a cube of wood

Here’s a challenge: 25 ml= ______ cubic cm Hint: 1 ml= 1 cc so 25 ml= 25 cc

25 ml= ______ cubic cm

Hint: 1 ml= 1 cc

so 25 ml= 25 cc

Practice measuring... Metric Lab Stations as needed

Metric Lab Stations as needed

Help available most days before school see me to make appt.

Help available most days before school

see me to make appt.

Scientific Notation Diameter of sun= 1,390,000,000 meters OR 1.39 x 10 9 meters Diameter of one helium atom= 0.000000000244 meters OR 2.44 x 10 -10 meters

Diameter of sun= 1,390,000,000 meters

OR 1.39 x 10 9 meters

Diameter of one helium atom= 0.000000000244 meters

OR 2.44 x 10 -10 meters