Transcript Document

Mr. Baldwin
PHYSICS
Mathematics & Measurement
9/9/2013
Aim: Why are rules and procedures important?
What is Physics?
Do Now: What is Physics? (Write some bulleted
point on what you think Physics is all about.)
Homework: Go to my page on www.whsad.org
Download, read, print and sign class contract,
and return it by Thursday 9-12-13.
Classroom Agenda
• Do Now
• Class Instructions
• Group Activity / Worksheets
• Class Reflection
• Bathroom passes will only be issued after classroom
instructions are finished
• (No issuance 10 mins. after & before bell).
• Derogatory & Offensive Language & tone of voice is
unacceptable.
Homework…
• Due at the beginning of the class on the assigned due
date.
• Absolutely No Excuses. Absolutely No LATE
homework will be accepted.
• Homework is to be done IN PENCIL on an 8 ½” x
11” white lined filler paper, smooth on all sides, and
written on one side only. Your name should be
written legibly in the top right corner of your
homework and stapled.
• A signed form from a parent/guardian is required to
make up any work.
Laboratory…
• All students taking Regents level courses are
required to meet the laboratory requirement
set forth by the NYS Commissioner of
Education.
• Failure to complete the 1200 minutes
laboratory assignments results in being barred
from taking the Regents Exam.
• Labs will be done in groups. Labs are to be
formally written up individually and returned
the following week.
• Any plagiarism shall count as a ZERO for
both parties involved.
MR. BALDWIN’S PHYSICS
LAB Grading RUBRIC
MISSING (mi):
No written lab submitted
INCOMPLETE (inc): Lab submitted but key components
(< 6.5 pts)
6.5 – 8 pts:
8.5 – 9 pts:
10 pts:
missing.
- missing calculations
- missing graphs
- questions/conclusion unanswered
Lab submitted with at least two (2)
components missing
Lab submitted with at least one (1)
components missing
Lab submitted and fully completed
MR. BALDWIN’S PHYSICS
ASSIGNMENT RUBRIC
MISSING (mi):
NO Assignment submitted
INCOMPLETE (inc): Assignment submitted with minimal
work done.
-
Homework format not followed
Problem solving format not followed
1 – 3: Weak attempt made/NO work shown
4 – 5: Fair attempt made/Little work shown
6 – 8: Good attempt made/Some work shown
9 – 10: Work is Complete & done to specification
classroom ruleS
Responsible for Your Work.
Every question is worth asking.
Speak with appropriate
Language.
Punctuality is a necessity.
Establish a positive
environment.
Come prepared to work & learn.
Take turns speaking.
Consequences
1. VERBAL WARNING
2. VERBAL WARNING & WRITTEN NOTATION
3. VERBAL WARNING, WRITTEN NOTATION &
STUDENT/TEACHER CONFERENCE
4. FAMILY GROUP ADVISOR/PARENTAL
NOTIFICATION
5. PARENT/FAMILY GROUP ADVISOR
CONFERENCE
6. REFERRAL TO ADMINISTRATION.
What is Physics?
Physics is a branch of science that involves the
study of the physical world: energy, matter, and
how they are related.
Learning physics will help you to understand the
physical world.
Physics uses mathematics as a powerful language.
In physics, equations are important tools for
modeling observations and for making predictions.
Mr. Baldwin
PHYSICS
Mathematics & Measurement
9/11/2013
Aim: What are standard units of measurement?
Do Now: A standard class period is
approximately a microcentury. How long, in
minutes, is a microcentury?
Homework: Worksheet 1.2 International System of
Measurement
Quiz 1: Prefixes (Let’s have phun)
Complete the quantity using the correct metric prefixes.
(ex. 1012 – tera, T; 1012 bulls = 1Tbull = 1 terabull)
1. 106 phones
2. 10-6 phones
3. 101 cards
4. 109 lows
5. 10-1 mates
6. 10-12 boos
7. 2 x 102 withit
8. 2 x 103 mockingbirds
12
Answers
1.
2.
3.
4.
5.
6.
7.
8.
M-phones (megaphones)
μ-phones (microphones)
Da-cards (deka cards)
G-lows (gigalows)
d-mates (decimates)
p-boos (picoboos)
2 h-withit ( 2 hectowithit)
2 k-mockingbird (2 kilomockingbird)
13
Subdivisions and Multiples of SI Units
14
METRIC PREFIXES
revised
These are the standard
SI prefixes for
indicating powers of 10.
CHECK
Can you give any
common everyday
examples where these
prefixes are used?
7 Basic Units of Measurement
In Physics, we
will be working
in the SI system,
where the basic
units are
kilograms,
meters, and
seconds (m.k.s).
Mr. Baldwin
PHYSICS
Mathematics & Measurement
9/12/2013
Aim: Why is the metric system easier to learn
than the British system?
Do Now: Write a short simple response to the
Aim above.(i.e. What are some of the
advantages of the metric system?)
Homework: Worksheet 1.2 International System of
Measurement (# 8-13)
Did you come up with something
like this?
The metric system is easy to use because all the
units are based on factors of 10.
Let’s see what you came up with?
7 Basic Units of Measurement
In Physics, we
will be working
in the SI system,
where the basic
units are
kilograms,
meters, and
seconds (m.k.s).
Definitions of Some Standard Units
Quantity Unit
Standard
Length
Meter
Length of the path traveled by
light in 1/299,792,458 second.
Time
Second
Time required for 9,192,631,770
periods of radiation emitted by
cesium atoms
Mass
Kilogram
A lump of Platinum cylinder in
International Bureau of Weights
and Measures, Paris
Examples of SI units include:
Can you give some examples of metric
units?
•
•
•
•
•
•
a. Volt (V) for voltage
b. Liter (L) for volume
c. Meters/second (m/s) for speed
d. Kilogram/meter3 (kg/m3) for density
e. Joule (J) for energy
f. Watt (W) for power
21
Converting Units
Converting between metric units, for example from
kg to g, is easy, as all it involves is powers of 10.
Converting to and from British units is
considerably more work.
Example: given that 1 m =
3.28084 ft, this 8611-m
high mountain is how
many feet high.
28250 feet
Mr. Baldwin
PHYSICS
Mathematics & Measurement
9/13/2013
Aim: How do we convert units between the
metric system and British system?
Do Now:
Given that 1 m = 3.28084
ft, this 8611-m high
mountain is how many feet
high? (write your answer
in scientific notation)
28250 feet
Section Check
Question
A car is moving at a speed of 90 km/h. What is the
speed of the car in m/s? (Hint: Use Dimensional
Analysis)
A. 2.5×101 m/s
B. 1.5×103 m/s
C. 2.5 m/s
D. 1.5×102 m/s
 90 km

 hr
  1000m   1hr


  1 km   60 min
  1min 

  25m / s
  60s 
Order of Magnitude: Rapid Estimating
A quick way to estimate a calculated quantity
is to round off all numbers to one significant
figure and then calculate. Your result should
at least be the right order of magnitude; this
can be expressed by rounding it off to the
nearest power of 10.
Section Check
Calculate approximately how many basketballs
(diameter = 75cm) can fit in this classroom
randomly AND orderly stacked one atop the other?
• LET’S WORK ON WORKSHEET
Mr. Baldwin
PHYSICS
Mathematics & Measurement
9/16/2013
Aim: Why are significant figures important?
(What is precision and accuracy?)
Do Now: How many seconds are there in a
year? Convert you answer to scientific
notation and round it off to 2 decimal places.
Homework:
Significant Figures
The number of significant figures is the number of
reliably known digits in a number. It is usually possible
to tell the number of significant figures by the way the
number is written.
Some Examples:
23.21 cm has 4 significant figures
0.062 cm has 2 significant figures (the initial zeroes
don’t count)
80 km is ambiguous – it could have 1 or 2 significant
figures. If it has 3, it should be written 80.0 km.
How many significant digits are in these
measurements?
a) 25.001 cm
________
b) 0.00012 kg
________
c) 35,000 m/s
________
d) 5.611 x 105 s
________
e) 0.0120 mm
________
f) 2.00 x 10-3 mL ________
g) 750 dg
________
Operations Involving Significant Figures
When multiplying or dividing numbers, the result
has as many significant figures as the number used
in the calculation with the fewest significant figures.
Example: 11.3 cm x 6.8 cm = 77 cm
When adding or subtracting, the answer is no more
accurate than the least accurate number used.
CHECK!
Can you create ONE example each of addition and
subtraction involving sig. figs.?
Check!
Which of the following representations is correct
when you solve 0.030 kg + 3333 g using scientific
notation?
A. 3.4×103 g
B. 3.36×103 g
C. 3×103 g
D. 3363 g
Accuracy & Precision
Define accuracy and precision?
OR
Create two sentences each using the words
precision and accuracy
• Accuracy is the proximity of measurement
results to the true value
• Precision, the repeatability, or reproducibility
of the measurement
Section Check
Read the following question and justify who gets
the most accurate and precise value
Ronald, Kevin, and Paul perform an experiment to determine the value
of acceleration due to gravity on the Earth (980 cm/s2). The following
results were obtained: Ronald: 961 ± 12 cm/s2, Kevin: 953 ± 8 cm/s2,
and Paul: 942 ± 4 cm/s2.
.
A. Kevin got the most precise and accurate value.
B. Ronald’s value is the most accurate, while Kevin’s value is the
most precise.
C. Ronald’s value is the most accurate, while Paul’s value is the
most precise.
D. Paul’s value is the most accurate, while Ronald’s value is the
most precise.
Answer: C
Reason:
Ronald’s answer is closest to 980
cm/s2, hence his result is the most
accurate.
Paul’s measurement is the most
precise, it’s within 4 cm/s2.
The precision of a measurement is one-half of
the smallest division of the instrument.
Formulate your OWN question
• Each person is to come up with a similar
question and have the person in front or
behind you answer the question.
• In the measurement, 86.21, the “2” is
(certain, estimated) and (significant, not
significant). The “1” is (certain, estimated)
and (significant, not significant).