Transcript I`ve never had a lab like this… Scientific Notation Workshop/Workday

Catalyst
January 7(5-3),
2011 HW OUT!
Check out the
‘graph’ to the
right.
Determine who the
“Biggest Rapper Alive”
is and back up with at
least 2 reasons (must
be from graph!).
Today’s Agenda
Catalyst
 Go over yesterday’s Exit Question/HW
 Sig Figs
 Intro to Dimensional Analysis
 Work Time
 Group of the Week and Exit Question

Book HW: Chapter 5 Review Questions
24, 26, 39, 40
Today’s Objectives
SWBAT determine the number of
significant figures in a number.
 SWBAT convert units like it’s
hot…by using dimensional
anlaysis.

Analyze
1 of the 12 Testing Power Words!

Example: Analyze the experimental
data to formulate a conclusion. Analyze
how the author uses personification.
 Break
down
 Figure out
 Scrutinize
 Interpret
Exit Question
Describe the accuracy
(A) and precision (P)
of 1 & 2.
What prefix/unit
would you use to
measure the
volume of cold
drink in a can?
What prefix/unit
would you use to
measure the
length of your
pinky?
Pop Quiz #2
1.
2.
3.
4.
How many significant figures are in the number
1457?
Round the following number to 2 significant
figures: 1.33
About how many pounds are in 1 kilogram?
1 dozen = 12 is an example of what two-word
term?
Significant Figures

1.
2.
Key Point #1: Know the Sig Fig Rules
starting on page 124!!! (esp. 1 & 2!!)
Nonzero integers always count as sig figs.
Ex: 1457 has 4 sig figs
There are 3 class of zeroes
a. Leading Zeroes (not sig figs) Ex: 0.0025
b. Captive Zeroes (are sig figs) Ex: 1.008
c. Trailing Zeroes (sometimes sig figs)
Ex: 100 vs. 100.
Counting Sig Figs: Examples
Give the number of sig figs for each of
the following measurements:

a.
b.
c.
d.
e.
0.045
3.402x102
49.2
4500
290.
Rounding Off Numbers

1.
Key Point #2: Know the Rounding Rules on page
126 (esp. 1!!)
If the digit to be removed…
a. is less than 5, the preceding digit stays the same
Ex: 1.33 rounds to 1.3
b.
is equal to or greater than 5, the preceding digit
is increased by 1
Ex: 1.36 rounds to 1.4
Ex: 3.15 rounds to 3.2
Ex: 4.57 rounds to 4.6
Rounding: Examples
Round the following numbers to 2 sig figs:

a.
b.
c.
d.
4.36
321
0.00563
2.09
Round the following numbers to 3 sig figs:

a.
b.
c.
d.
6389
4082
0.02751
2.198x10-3
CONVERSIONS

GET READY FOR AWESOME!
Convert it like it’s hot

Key Point #3: A conversion factor
shows the same value with two
different units.
 YOU
ALREADY KNOW THIS STUFF!
 Examples:
 10
dimes= 1 dollar
 20 nickels= 1 dollar
 4 quarters= 1 dollar
Dimensional Analysis

Key Point #4: Dimensional
analysis is a tool used to
convert from one unit to another.
Working on the Railroad

Step 1:
What

Step 2:
Write

to what?
conversion factor(s)
Step 3:
Train
tracks
Practice! One-step problems.


How many meters are in 10
centimeters?
How many centimeters are in 327
meters?
Practice! On your own!

The distance from
New Orleans to
Miami is 1387
kilometers (862
miles). Convert
1387 kilometers
to meters!
Exit Question

In July 2008, it was estimated that the
world’s population is about 6,707,000,000.
The United States’ population was estimated
to be 304,060,000. The coldest temperature
ever created by man is 0.000000005 Kelvin.
Write the 3 bolded numbers in scientific
notation and determine the number of sig figs
for each.