Measurements Chapter 3 Mr. Smith's Coggle Map
Measurement
Definition
a quantity that has both a number and a unit
Scientific Notation
Short hand way of writting very large or small numbers.
Examples:
6.02 x 10^23
1.98 x 10^-21
Positive Exponent = big number
Negative Exponent = small number
Accuracy
how close it comes to the actual target/number
Precision
Error
how close a series of measurements are to one another
accepted value
Experimental value
Value measured many times for a constant value.
measured in a lab
Error = Experimental Value - Accepted Value
Percent Error = ([error] \ accepted value) x 100%
Significant Figures
3. Left handed Zeros
4. Right handed Zeros
2. Zero Sandwich
1. Non Zeros
5. Weird Zeros
Every nonzero number is significant
Examples:
7,432 = 4 sig figs
24.7 = 3 sig figs
Zeros between nonzero numbers are significant.
Examples:
7,003 = 4 sig figs
400.79 = 5 sig figs
104 = 3 sig figs
zeros appearing to the left of the first nonzero number are not significant.
Examples:
0.42 = 2 sig figs
0.0071 = 2 sig figs
0.000 000 009 = 1 sig fig
Zeros at the end of a number that are right of the decimal are significant
Examples:
8.40 = 3 sig figs
56.0000 = 6 sig figs
1.010 = 4 Sig Figs
Zeros that appear at the end of the number BUT before the decimal would be...when no decimal is present
Examples:
40,000 = 1 sig fig
146,670 = 5 sig figs
300 = 1 sig fig
Illustration:
Accuracy v. Precision
International System of Units (the SI System)
Updated version of the Metric System
Based on multiples of 10, making conversions very easy to figure out
Uses Prefixes and Units
Common Base Units
Gram (g) - mass
Kelvin (K) - Temperature
Second (s) - Time
mole (mol) - Substance Amount
Liter (L) - Volume
Meter (m) - Length
Common Prefixes
Deka (D) - 10 base units
Base UNIT = 1 base unit
Hecto (H) - 100 base units
deci (d) - 1/10th base unit
centi (c) - 1/100th base unit
milli (m) - 1/1000th base unit
Kilo (K) - 1,000 base units
Temperature Scales
Kelvin
Fahrenheit
Celsius
Water Freezes at 0 degrees C
Water Boils at 100 degrees C
Water Freezes at 32 degrees F
Water Boils at 212 degrees F
Water Freezes at 272.15 K
Water Boils at 373.15 K
Joule (J) - Energy
Amperes (amps) - Current
Conversion Chart
K H D (unit) d c m