Transcript Phy Sci ScientificNotation(2) - BiologyIsFun

Pre Class: Thu. 9.23.10
• ID in the cart and get your laptop.
• Username: Student Password:
Student.
• www.empower3000.com
• Work on “A Hands on Study”. And
“Don’t Want the Flu…”
– Read then do the Activity, Thought and
Poll Questions for each article.
• I am collecting HW!!!
In your notebook:
• From what you read in “Don’t Want the
Flu?”
– The scientists studied the survival rate of
the flu virus in dry and humid air.
• What was the control group? The experimental
group?
• The independent variable? Dependent variable?
When/If you are done with both
articles…
• https://biologyisfun.wikispaces.com
• On the left side click on “Powerpoints
Phy Sci”.
• Open the presentation called “Phy Sci
Scientific Notation”. And take notes
and complete the practice problems.
Pre Class: Friday 9.24.10
• Take a Quiz.
– Answer #1-10 (#10 is on the back).
– You may write on the quiz.
– Ch. 1 Test Friday 10.1.10
Scientific Notation- used to
express numbers that are very
large or very small. Reduce the
number of zeroes and express a
simple number multiplied by a
power of 10.
 0806.2.1
Recognize and use scientific
notation.
When using Scientific Notation, there are
two kinds of exponents: positive and
negative
Positive Exponent:
2.35 x 108
Negative Exponent:
3.97 x 10-7
Standard Notation to Scientific
Notation!
1) First, move the decimal after the first whole
number:
3258
2) Second, add your multiplication sign and
your base (10).
3 . 2 5 8 x 10
3) Count how many spaces the decimal moved
and this is the exponent.
3 . 2 5 8 x 10 3
3 2 1
Using Scientific Notation…
1) Move the decimal point to the right
or left until you have a number that
is greater than or equal to 1, but
less than 10.
2) Count how many places you moved
the decimal point. This number
will become the absolute value of
the exponent.
3) If you moved the decimal point to
the left, the exponent will be
positive.
4) If you moved the decimal point to
the right, make the exponent
negative.
Scientific Notation to Standard
Notation
-Exponent tells how many spaces to move
the decimal point.
With a positive exponent, move the
decimal to the right:
4.08 x 103 = 4 0 8
Don’t forget to fill in your zeroes!
Scientific Notation to Standard
Notation.
-Exponent tells you how many places to
move the decimal.
With a negative exponent, move the
decimal to the left:
4.08 x 10-3 =
408
Don’t forget to fill in your zeroes!
Try changing these numbers from
Scientific Notation to Standard Notation:
1) 9.678 x 104
96780
2) 7.4521 x 10-3
.0074521
Try changing these numbers from
Standard Notation to Scientific Notation:
1) 9872432
9.872432 x 106
2) .0000345
3.45 x 10-5
Multiplying and Dividing with
Scientific Notation.
• (5.5 X 10^4 cm) X (1.4 X 10^4 cm).
• Multiplication = add the exponents.
• 5.2 X 10^8 cm^3 / 9.5 X 10^2 cm
• Division = subtract the exponents.
Practice on Your Own…
• Complete the scientific notation
problems #1-16 in the Metric
Mania Packet.
• HW: Read p. 20-24. Practice p.23
#1-2. Practice p. 24 #1-2. Section
Review p. 26 #1-2 and Math Skills
# 5-6.
Friday Fun!-- Mythbusters.
• Review of the scientific method,
controls, variables, lab safety and
reliable results.
• Answer the questions in your notebook.
Pre Class: Monday 9.27.10
• Take a Constructed Response
Sheet, a piece of loose leaf and a
Weekly Schedule.
• Answer Parts A and B in complete
sentences on the loose leaf paper.
• I am checking HW!
Recap Sci. Notation HW.
1. 800,000,000 m
Answer: 8 X 10^8 m
b. 0.0015 kg
c. 60,200 L
Answer: 1.5 X 10^-3 kg
Answer: 6.02 X 10^4 L
d. 0.00095 m
Answer: 9.4 X 10^-4 m
e. 8,002,000 km
Answer: 8.002 X 10^6 km
f. 0.00000000006 km
Answer: 6 X 10^-11 kg
Recap HW: Sci. Notation to long
form.
2. 4.5 X 10^3 g
Answer: 4,500 g
b. 6.05 X 10^-3 m
Answer: 0.00605 m
c. 3.115 X 10^6 km
Answer: 3,115,000 km
d. 1.99 X 10^-8 cm
Answer: 0.0000000199 cm
Significant Figures
Monday 9.27.10
Significant Figures- Why do we
care?
• To show the precision of a
measured quantity.
• Precision- exactness of a
measurement. (Repeatability)
• Accuracy- how close a
measurement is to the true value
of the measured quantity.
Accuracy and Precision
Sig. Figures
• 1100 grams
• 1100.0 grams
• Which is more precise?
• Only deal with measured values!
Significant Figures- Rules.
• 1. Non zero digits are ALWAYS
Significant. (22.4567- 6 Sig. Figs)
• 2. Any zeroes between two Sig.
Figs. Are significant. (22.507- 5 Sig
Figs)
• 3. A final zero in the decimal
portion ONLY are significant (2.30
X 10-5-- 3 Sig. Figs)
Other types of Zeroes.
• Place holding zeroes are NEVER
significant. (.00500 --3 Sig Figs)
– When you write this in Sci. Notation the
non-significant zeroes disappear.
• Zero to the left of a decimal point
is NEVER significant.
– Its only there to let you know that it is a
decimal and not a period! (0.00500)
Other types of Zeroes.
• Trailing zeroes in a whole number
are NOT significant. (200 -- 1 sig
fig).
Leading zeroes in a whole
number are NOT significant.
(00250-- 2 sig figs).
On your own…
• Work on the Front side of the
sheet. #1-13.
• If you are finished, start the back.
Wrap It Up!
• Exit Ticket: Why are significant
figures important?
• HW: finish the back of the
worksheet.
Pre Class: Tuesday 9.28.10
In your notebook:
– A 4.00 kg rock’s mass is measured several
times. Which set of measurements below is
precise but not accurate? Explain why! (you
can use your notes!) (2-3 sentences).
• A. 3.5 kg, 2.5 kg, 4.5 kg
• B. 3.55 kg, 3.57 kg, 3.56 kg
• C. 3.99 kg, 4.02 kg, 4.00 kg
• I am checking your HW:)
Recap HW: #1-45, #76-83, #88102.
• Take 7 min and discuss your
answers with a partner.
• Together, also answer #11, 12,
and 13 on the front side of the
sheet.
• Be ready to share your answers
with the class.
Addition and Subtraction with
Sig. Figs.
• Rule: the answer cannot be more
precise than the values in the calculation.
– You have to round the answer to the #
of sig. figs. Of the least precise value.
• Example:
• 6.3421 s + 12.1 s = 18.4421 s
– Round to correct # of sig. figs: 18.4 s
Practice on your own: (Make sure you
round to the correct # of sig figs.)
• A. 1.23 g + 4.567 g =
• B. (1.23 x 10^6 mm) + (4.567 x 10^6
mm) =
• C. 54.20 cm - 22 cm =
• D. (4.220 x 10^-6) - (9.963 x 10^-7) =
– This one is tricky! Make sure both #’s have the
same exponents before subtracting the two
lead numbers! Don’t subtract the exponents!
Wrap It Up!
• Exit Ticket: #1-7 Mythbusters
review of scientific method, etc.
• HW: Finish Sig. Figs. Practice
Packet.
Pre Class: Wed. 9.29.10
• Get your portfolio.
• ID in the cart and get your laptop.
• Sign on to lap top: Username: Student
Password: Student.
• www.empower3000.com
• Work on “No Water? No Problem”
– Read then do the Activity, Thought and Poll
Questions for each article.
• I am collecting HW!!!
When you are done…
• Review assignment:
– Textbook p.27 Practice #1 (Pie chart)
– P.28 Understanding Concepts #1-15.
– P.29 Building Math Skills: #22 and 26.
Wrap It Up!
• Exit Ticket: Return Laptop and get
your ID.
• HW: Finish “No Water? No Problem.”
• Log on to Empower3000 at home
and change your avatar and check
out the games section.