Basic Units Length meters Mass kilograms Time seconds

Basic Units • Length meters • Mass kilograms • Time seconds

• Temperature Kelvin • Amount Chm Mole • Current Amphere • Luminous In Candela

Metric Prefixes >1 • Mega (M) • Kilo (k) • Milli (m) <1 Micro (m) Nano(n) Pico (p)

Metric Prefixes >0 9 • (G) = 10 6 • (M) = 10 3 • (k) = 10

Metric Prefixes <0 -3 • (m) = 10 -6 • (m) = 10 -9 • (n) = 10 -12 • (p) = 10

Accuracy • How close you are to the real answer

Precision • How well one can repeat his or her work • Repeatability

Uncertainty • All measurements have a degree of unreliability • Usually in the last digit of a measurement

Significant Digits • Meaningful digits in a number

Multiplication Uncertainty • The answer should have the same number of significant digits as the multiplier with the least number of SD • Same for division

Addition Uncertainty • When adding, line up decimal place & add • The decimal places in the answer should = the least • Same for subtraction

Determining Significance • All non-zero digits • All zeros between non-zero numbers • All trailing zeros if there is a decimal place

When do you leave Sig Figs alone? • Numbers obtained by counting or by definition are exact numbers. –# of students in the classroom – 2. 54 cm = 1 inch

PERIOD 4 stopped here

Scientific Notation • M x • M = 1. 00 M < 10. 00 • n = an integer n 10

Conversion Factor • Ratio equal to one • 12 inches/1 foot • Multiply one unit by a conversion to obtain another unit w/o affecting magnitude

• PERIOD 4 LEFT OFF HERE

Convert: • 2. 50 cm to Mm • 4. 2 ns to ms • 3. 15 kg to mg

Determine the length in miles of a light year • Light year = distance light travels in one year 8 • c = 3. 0 x 10 m/s • 1 mile = 5280 ft • 1 inch = 2. 54 cm