Math: The Central Language of Science
Math: The Central Language of Science
Physics - Chapter 2
Types of measurement
1 _________________________ - use numbers to describe
1 Easy to _______________________
2 Easy to ________________ upon, no personal bias
3 The measuring instrument limits how good the measurement is
2 _________________________ - use description without numbers
Measurements - Quantitative
1 Unit of measurement – the _____________________ being measured
2 Pure number – the __________________ of units determined by the act of measuring
3 ___________________ – the product of the pure number and the unit of measurement
Your Turn to Decide: Quantitative or Qualitative
1 4 feet
2 extra large
3 Hot
4 100 ºF
5 Sunny
6 96
Système International d’Unités
1 SI Units – the _______________ system
2 ______________ base units
1 mass, length, time, mol, temperature, electric current, luminous intensity
3 Many __________________ units
1 Density, volume
Base Units
1 Mass – ________________ (kg)
2 Length – meter (______)
3 ______________ – second (s)
4 Amount of substance – mole (___________)
5 Temperature – _________________ (K)
6 Electric Current – _________________ (A)
7 Luminous Intensity – __________________ (cd)
Derived Units
1 _______________ = mass ÷ volume
2 Volume = length • width • height
3 _________________ = Newton • length
4 Newton = mass • _________________
5 _________________ = length ÷ time squared
Dimensional Analysis
1 ________________________ from one unit to another
2 Conversion Factor – a ____________________ (ratio) comparing two units
1 Examples:
1 12 inches = 1 foot
2 3 feet = 1 yard
3 100 cm = 1 m
4 60 s = 1 min
3 Conversion factors can be __________________!!
Grid Method for Conversions
Grid Method for Conversions
Grid Method for Conversions
Dimensional Analysis
How good are the ___________________________________?
1 Scientists use two words to describe how good the measurements are
1 _____________________________- how close the measurement is to the actual value
2 _____________________________- how well can the measurement be repeated
Differences
1 Accuracy can be true of an ________________ measurement or the average of several
2 Precision requires ________________ measurements before anything can be said about it
In terms of measurement
1 Three students measure the room to be 10.2 m, 10.3 m and 10.4 m across.
2 Were they precise? __________________
3 Were they accurate? __________________
The Metric System
1 An easy way to measure
17 Converting
k h D d c m
1 how far you have to move on this chart, tells you how far, and which direction to move the decimal place.
2 The box is the base unit, meters, Liters, grams, etc.
Significant figures (sig figs)
1 How many numbers mean anything
2 When we measure something, we always _______________ between the smallest marks.
3 The better marks the better we can estimate.
4 Scientist always understand that the last number measured is actually an estimate
Sig Figs
1 All _________________ numbers are ________________!
2 So….what do we do with zeros??
3 We follow the _________________!
Significant Digit Rules
1 Only applied to ____________________ data.
1 _____________________ numbers are infinitely significant!
2 All ________________ digits are _____________________!
3 All zeros ______________________ nonzero digits are significant!
4 In a ___________ number all zeros to the _______ of the last nonzero digit are significant!
5 In a decimal number all zeros to the _____ of the first nonzero digit are ______ significant!
6 In a number _________________ a decimal all trailing zeros (zeros to the right of the last nonzero digit) are _______________ significant!
Remember….
1 Scientific Notation only shows significant digits in the decimal part of the expression.
2 A decimal point following a zero at the end of the number indicates that the zero is significant.
Problems
1 50 has only 1 significant figure
1 if it should have two, how can I write it?
1 A __________________________ following a zero at the end.
2 ____________
2 A line over the significant zero
i) 50
3 Scientific notation
1 5.0 x 101
1 now the zero counts
How many sig figs in the following measurements?
5 458 g
6 4085 g
7 4850 g
8 0.0485 g
9 0.004085 g
10 40.004085 g
11 405.0 g
12 4050 g
13 0.450 g
14 4050.05 g
15 0.0500060 g
Rules for calculations with Significant Digits
23 Adding and Subtracting with Sig Figs
1 The last sig fig in a measurement is an _________________________.
2 Your answer when you add or subtract can not be better than your _________ estimate.
3 ___________ the answer to the least precise place of the measurement in the problem
Rounding rules
1 round 45.462 to four sig figs _________________
2 to three sig figs _____________________
3 to two sig figs _____________________
4 to one sig fig ______________________
Practice
1 4.8 + 6.8765
2 520 + 94.98
3 0.0045 + 2.113
4 6.0 x 102 - 3.8 x 103
5 5.4 - 3.28
6 6.7 - 0.542
7 500 -126
8 6.0 x 10-2 - 3.8 x 10-3
Multiplication and Division
1 Rule is simpler: Same number of sig figs in the answer as the one with the least number of sig figs in the question
2 3.6 x 653
1 2350.8
3 3.6 has 2 s.f. 653 has 3 s.f.; answer can only have 2 s.f.
4 2400
Practice
1 5.345 • 3.9
2 4.5 ÷ 6.245
3 4.50 • 6.245
4 9.8764 • 0.043
5 3.876 ÷ 1983
6 16047 ÷ 700
7 2400 • 123
8 4.5 x 102 • 1.45 x 103
What about angles and trigonometry
a) SI Unit is ___________________
b) Radian – the plane angle that subtends a circular arc equal to length to the radius of the circle
c) _____________ = _________________
d) Angles measured with a protractor should be reported to the nearest ________________
1) Conversions:
a) Report angles resulting from trig calculations to the ______________ precision of any angles given in problem
b) Assume trig ratios for angles given are pure numbers and do not take into account _____________
Instruments
30 Tools used to _________________
31 ______________ to modern scientific research
32 _____________________________
Error
34 The simple ______________ of the ___________________ and ___________________ values
35 May be __________ or __________
36 Absolute Error - _____________________ of the difference
Percentage Error
Problem Solving
40 Read CAREFULLY!
41 What information is _________________?
42 What information is _________________?
43 Make a ______________ _____________
44 Determie the method of _____________________
45 ________________ and _________________
46 Check your answer for ___________________
47 Does it have the expected __________________ and ______________?
48 Make a mental ________________
49 Be sure to simplify ________________
50 Express results to the correct number of ____________
................
................
In order to avoid copyright disputes, this page is only a partial summary.
To fulfill the demand for quickly locating and searching documents.
It is intelligent file search solution for home and business.
Related download
- chemistry 11 problem solving in chemistry
- significant figures practice worksheet
- oklahoma city community college
- guided notes on accuracy precision and significant
- significant figures uncertainty in measurement
- significant figures a
- unit 1 metric system significant figures factor label
- math the central language of science