Scientific measurement_metric_system.ppt

Measurement system (the metric system), to student grade 7, Junior High school

1. SCIENTIFIC SCIENTIFIC
MEASUREMENTMEASUREMENT
International System of UnitsInternational System of Units (SI) - (SI) -
measurement system used by scientists measurement system used by scientists
around the world to express around the world to express
measurements made in scientific measurements made in scientific
investigations [the Metric System].investigations [the Metric System].
[THE METRIC SYSTEM]

2. 
Scientists Scientists all over the world all over the world know and know and
use the metric system.use the metric system.

3. 
Below is a list of the basic units of Below is a list of the basic units of
the the metric systemmetric system (SI system) and (SI system) and
the commonly used prefixes with the commonly used prefixes with
their meanings.their meanings.

4. What units are used when What units are used when
measuring objects?measuring objects?

Basic SI units:Basic SI units:
–meters (m) - meters (m) - lengthlength
–grams (g) - grams (g) - massmass
–liters (L) – liters (L) – volumevolume
–seconds (s) – seconds (s) – timetime
–Celsius degree (Celsius degree (
oo
C.) – C.) –
temperaturetemperature

Prefixes: see table Prefixes: see table →→

The metric system is used The metric system is used
for for all over the world all over the world
((exceptexcept the USA) the USA)

Used for Used for all all SCIENTIFIC SCIENTIFIC
measurements (incl. the measurements (incl. the
USA)USA)

SISI stands for… stands for…
Systeme InternationaleSysteme Internationale

5. BASIC UNITS OF THE BASIC UNITS OF THE
METRIC SYSTEMMETRIC SYSTEM
BASIC UNITBASIC UNIT PROPERTY PROPERTY
MEASUREDMEASURED
meter (m)meter (m) lengthlength
gram (g)gram (g) MassMass
liter (L)liter (L) VolumeVolume
second (s)second (s) TimeTime
Celsius degree (CCelsius degree (C
oo
)) temperaturetemperature

6. COMMON PREFIXES AND COMMON PREFIXES AND
THEIR MEANINGSTHEIR MEANINGS
PREFIX PREFIX
(abbreviation)(abbreviation)
MEANINGMEANING
kilo – (k)kilo – (k) 1,000 ( 1 thousand)1,000 ( 1 thousand)
hecto – (h)hecto – (h) 100 (1 hundred)100 (1 hundred)
deca- or deka- (da or deca- or deka- (da or
dk)dk)
10 (ten)10 (ten)
deci- (d)deci- (d) 0.1 ( tenth)0.1 ( tenth)
centi- (c)centi- (c) 0.01 (1 hundreth)0.01 (1 hundreth)
milli- (m)milli- (m) 0.001 (1 thousandth)0.001 (1 thousandth)

7. How are we going to How are we going to
remember this???remember this???

KingKing

Henry’s Henry’s

darneddarned

MONEY (GOLD, LOOT)MONEY (GOLD, LOOT)

didn’t didn’t

comecome

Monday.Monday.

8. How do we convert in the How do we convert in the
Metric system?Metric system?

Walk along the “Metric Sidewalk…..”Walk along the “Metric Sidewalk…..”

9. THE METRIC SIDEWALK:THE METRIC SIDEWALK:
k h da or dk (unit) d c m
-Move decimal point to the Move decimal point to the RIGHTRIGHT
if you walk to the RIGHT.if you walk to the RIGHT.
- Move the decimal point to the Move the decimal point to the
LEFT if you walk to the LEFT if you walk to the LEFTLEFT..

10. PRACTICE:PRACTICE:
1.1.23.675 cm = _____________ hm23.675 cm = _____________ hm
2.2.56 dm = _____________ cm56 dm = _____________ cm
3.3.14.356 mg = _____________ hg14.356 mg = _____________ hg
4.4.12 kL = _____________ L12 kL = _____________ L
5.5.6.98 hg = _____________ mg6.98 hg = _____________ mg
6.6.9 m = _____________ km9 m = _____________ km
7.7.6.854 cL = _____________ kL6.854 cL = _____________ kL
0.0023675
560
0.00014356
12,000
698,000
0.009
0.00006854

11. More Practice:More Practice:
8.8.3.65 mg = _____________ dg3.65 mg = _____________ dg
9.9.9.987 g = _____________ hg9.987 g = _____________ hg
10.10.12.203 km = _____________ mm12.203 km = _____________ mm
0.0365
0.09987
12,203,000

12. More Practice! Quiz
Tomorrow!!!
1. 8.92 m = ________________ cm
2. 5000 cm = _______________ m
3. 5 km = __________________ m
4. 39,000 hm = _____________ m

13. Even more practice!
Kim and Meghan live on opposite
sides of town. On Sundays they ride
their bicycles and meet at the soccer
field. Kim rides 2.3 km, and Meghan
rides 2129 m.
–(a) Who has the longer ride? __________
–(b) How did you figure this out.

14. Temperature ScalesTemperature Scales

Fahrenheit – used in USAFahrenheit – used in USA

FP of water = 32 FP of water = 32
oo
F.F.

BP of water = 212 BP of water = 212
oo
F.F.

Room temp. = 67 Room temp. = 67
oo
F.F.

Body temp. = 98.6 Body temp. = 98.6
oo
F.F.

15. Temperature ScalesTemperature Scales

Celsius (Centigrade) – used Celsius (Centigrade) – used
everywhere elseeverywhere else

FP of water = 0 FP of water = 0
oo
C.C.

BP of water = 100 BP of water = 100
oo
C.C.

Room temp. = 20 Room temp. = 20
oo
C.C.

Body temp. = 37 Body temp. = 37
oo
C.C.

16. Temperature ScalesTemperature Scales

Kelvin – degrees above Kelvin – degrees above absolute zeroabsolute zero

FP of water = 273 FP of water = 273
oo
C.C.

BP of water = 373 BP of water = 373
oo
C.C.

0 K = -273 0 K = -273
oo
C.C.

O K = -460 O K = -460
oo
F.F.

17. Measuring MassMeasuring Mass

Triple-beam balanceTriple-beam balance

First zero the balanceFirst zero the balance

Move sliders; make it balanceMove sliders; make it balance

Measure to nearest 0.01 gMeasure to nearest 0.01 g

18. How could you measure How could you measure
the the mass mass of a liquid?of a liquid?

Step 1 – Step 1 –

Step 2 – Step 2 –

Step 3 – Step 3 –

Step 4 – Step 4 –

Step 5 –Step 5 –

Meas. mass of Meas. mass of
grad. cylindergrad. cylinder

Put liq. inPut liq. in

Meas. mass of Meas. mass of
grad. cyl. plus liq.grad. cyl. plus liq.

SubtractSubtract

Add correct unitsAdd correct units

19. Measuring Volume of a liquidMeasuring Volume of a liquid

Graduated cylinderGraduated cylinder

NOT a beaker!!!!!NOT a beaker!!!!!

Read at eye levelRead at eye level

Bottom of meniscusBottom of meniscus

1 ml = 1 cm1 ml = 1 cm
33

20. Measuring Volume of a solidMeasuring Volume of a solid

Cube: V = lCube: V = l
33

Right rectangular prism: V = l w hRight rectangular prism: V = l w h

Cylinder: V = (4/3) Cylinder: V = (4/3) ππ r r
22
h h

Cone: Cone: V = (1/3) V = (1/3) ππ r r
22
h h

Sphere: V = (4/3) Sphere: V = (4/3) ππ r r
33

Irregular solid: use the water Irregular solid: use the water
displacement method!displacement method!