Basic Units Length meters Mass kilograms Time seconds
Basic Units • Length meters • Mass kilograms • Time seconds
• Temperature Kelvin • Amount Chm Mole • Current Ampere • Luminous In Candela
Metric Prefixes • Mega(M) • Kilo(k) • Milli(m) • Micro(m) Nano(n) Centi(c)
Metric Prefixes • (M) = (n) = 3 • (k) = 10 -3 -2 • (m) = 10 (c) = 10 -6 • (m) = 10 6 10 -9 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
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
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
Convert: 4. 35 kg/L to mg/m. L 2. 31 mm/ns to cm/Ms
Calculate the volume 3 in m occupied by 750 kg of gas with 1. 50 g/L 3 1 cm = 1 m. L
Calculate the mass in kg of a board that has dimensions of 250 mm x 4 4. 0 x 10 mm x 2. 5 m and had a density of 0. 80 g/m. L 3 1 ml = 1 cm
Calculate the density 3 of a 3. 14 x 10 kg cylinder that 5. 0 m long & has a diameter of 2. 0 m.
How many nm will an object travel in 1/132 ks at 720 miles per hour 1 inch = 2. 54 cm 1 mile = 5280 ft
Measurements • Work problems 5 - 12 on page 23
Sig. Figs. • Work problems 17 - 24 on page 23
Conv. Factors • Work problems 28 & 36 on page 24
Measurements • Work problems 5 - 12 on page 25
Define all the key terms on page 24
Work problems 13 - 16 on page 25
Conversion Factors • Work problems 37 - 46 on page 25
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