1. Chapter 1 Glencoe Physics Principles & Problems
Physics Toolkit
Chapter 1
Glencoe Physics
Principles & Problems

2. Learning Objectives Know the SI system base units
Know what significant figures are and how to determine s.f. for multiplication/division and addition/subtraction
Read a graph to find slope
From graph shapes determine relationships
Convert within the metric system & to English system & vice versa
Convert using dimensional (unit) analysis
From math equations, determine relationships
Solve problems using order of magnitude and percent error
Basic statistics

3. Assignments for Ch 1 Read notes online
Read chapter 1 and write Reflections (see your syllabus)
Questions and problems from book: 1-12, 30, 31, 36-38, 42,45,46, 67-74

4. International System (SI)
A. Quantities and base units of measure
length – meter, m
temperature – Kelvin
mass – gram
time – second
B. Derived quantities and units
electric current – ampere
weight – force with which gravity pulls on a quantity of matter – Newton is the unit

5. Significant figures – determined by the equipment used to collect data.
Numbers are read directly from the equipment plus 1 estimated digit.
When multiplying several numbers, the number with the least significant digits determines how many digits are written in the answer.
Sample: cm x cm x cm has only 3 significant figures so the answer will also.
The answer is Round to 7.39 cm3.

6. Graph Interpretation
“Directly proportional”
“Inversely proportional”

7. slope = rise / run
slope = 6 m/s / 4 s
slope = 1.5 m/s/s
(or slope = 1.5 m/s2)

8. Systems of measurement
Weight = Mass x Acceleration*
SI/mks
Newton Kg
9.8 m/s2
cgs
dyne G
980 cm/s2
English
pound
32 ft/s2
mks (meter-kg-sec) or International System (SI)
cgs (cm-g-sec)
*Acceleration due to gravity

9. English to Metric Conversion problem
Convert your weight to metric weight where 1 kg = 2.2 lb.
130 lb 1 kg = 59 kg
2.2 lb
Using weight = mass x gravity
mg = 59kg(9.8m/s2) = = 5.8 x 102 n

10. Unit analysis Conversions Weight: 2.2 lb = 1kg Length: 1.0 in = 2.54cm
5280 ft = 1 mile
0.625 mile = 1 km
Volume: 1.06 qt = 1.0 L
30. mi = ? Km
gal L
30. mi 1km gal qt = = 13 = 1.3 x 101 km
gal mi 4 qt L L

11. Math relationships in equations
F = G m1 m2 d2
F a m F a 1/d2

12. Order of Magnitude - solving problems by using powers of 10
800, (4200)
( )
106 (103) = 109 = 109-(-6)
10-3 (10-3)
Answer: 1015

13. Percent Error
A chemist tests the boiling temperature of a chemical and finds it to be 137.2oC. The accepted value is 135.9oC. What is the percent error?
% Error = / Vo - Va/ x 100 = 137.2oC oC
Va oC
% Error = %

14. Basic statistics
Mean, x - arithmetic average (not used in stats involving income - influenced by extreme values)
Median - middle value (used with salaries)
Mode - most common value (shoe stores purchase most common sizes)
Sample: test scores of 94,96,98,96 (your grades in Physics!)
Mean, x = = 96 4
Median = 96  middle
Mode = 96  most common
x is pronounced
“x bar"