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Section 3B Putting Numbers in Perspective. Pages 154-171. 3-B. Scientific Notation. Absolutely critical for very large and very small numbers Ex1/155 The federal debt is $9,100,000,000,000. The diameter of a hydrogen nucleus is 0.0000000000000001 meter.
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Section 3BPutting Numbers in Perspective Pages 154-171
3-B Scientific Notation Absolutely critical for very large and very small numbers Ex1/155 The federal debt is $9,100,000,000,000. The diameter of a hydrogen nucleus is 0.0000000000000001 meter. Your calculators automatically use it!
3-B Scientific Notation Scientific Notation is a format in which a number is expressed as anumber between 1 and 10multiplied by a power of 10. Examples: 9,100,000,000,000 = 9.1 1012 = 9.1 E 12 (calculator) 0.0000000000000001 =1.0 1016 =1 E -16 (calculator)
3-B Scientific Notation 106 = 1 million = 1,000,000 109 = 1 billion = 1,000,000,000 1012 = 1 trillion = 1,000,000,000,000 • The U.S. federal debt is about $9.1 trillion ($9.1×1012)
3-B Ordinary vs Scientific Notation An exercise in powers of 10 and moving the decimal KEY: X 10(positivep) moves decimal p places to right. X 10(negativep) moves decimal p places to left.
3-B Conversion from scientific to ordinary Examples: 1.7842 103 = 1784.2 2.111 107 = 21,110,000 9.1 10-4 = .00091
3-B Conversion from ordinary to scientific Example: 1330 = 1.330 103 .00000345 = 3.45 10-6 527 103 = 5.27 102 103 = 5.27 105
3-B Using your Calculator Look for an “EE” key 1.7842 103 1.7842 EE 3 = 1784.2 2.111 107 2.111 EE 7 = 21110000 9.1 10-4 9.1 EE -4 = 0.00091 1000 = 1.0 x 103 1.0 EE 3 not (10) EE 3
More Practice 25/164 Convert from scientific to ordinary 27/164 Convert from ordinary to scientific. 33/164 Total annual energy consumption in the US is about 100,000,000,000,000,000,000 joules. 35/164 The hard drive on my computer has a capacity of 12.0 gigabytes (recall ‘giga’ = billion). 37/164 The diameter of a typical bacterium is about 0.000001 meter.
3-B Multiply or Dividing with scientific notation: Examples: 6200 x 300000 (6.2 103)× (3 105) = (6.2×3)×(103×105) = 18.6×10(3+5) = 1.86×10 x 108 = 1.86 x 109 420 4.2 102= 4.2× 102 .000084 8.4 10-5 8.410-5 = .5×102-(-5) = .5×107 = 5.×10(-1) x 107 = 5.0 x 106 More Practice 29/168
3-B Why Scientific Notation: Approximations Example: 14927 2213 ≈ 15000 × 2000 = (1.5×104)× (2 × 103) = 3×107 = 30,000,000 (30 million) check: 14927 2213 = 33,033,451 More Practice: Ex2/1558 million residents produce 1.8 lb or .0009 tons of trash each day. Estimate the total amount of trash produced each day. [225 tons?]
3-B Why Scientific Notation: Calculator Issues Total annual energy consumption in the US is about 100,000,000,000,000,000,000 joules. Convert to kilowatt-hours. = .278 x 1014 = 2.78 x 10(-1) x 1014 = 2.78 x 1013
Homework: Pages 168 # 26 28, 34, 36, 38, 40