Chapter 1: Measurements and
DImensional Analysis

Units

Kilograms

mass

Meters

Seconds

Charge of an electron = 1.602 x 10^-19 Coulumb

length

volume

density = mass/volume #

helpful things about units

1 kg = 2.2046 pounds

1 inch = 2.54 cm exactly

Celsius (Kelvin)

about pi x 10^7 seconds in one year

density of water = 1 g/cm^3 = 1000 kg/m^3

WolframAlpha

density of air (sea level) is 1/1000-th of water

What is the volume of this classroom?

What is the mass of air in this classroom?

speed of light = 3 x 10^8 m/s

How far will light travel in one year?

Convert 1 femtolight year to yards (football)

prefixes

giga = 10^9

mega = 10^6

human civilization uses 15 terawatt (2017)

What is the volume of 1 meter times area of the oceans?

tera = 10^12

micro = 10^-6

nano = 10^-9

pico = 10^-12

femto = 10^-15

humans just barely float in water: density = 1 g/cm^3

Significant Digits

multiplication

exact numbers

addition

Precision and Accuracy

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Energy

kinetic energy

potential energy (work)

chemical energy