1. yes 2. no accuracy - how close a measurement is to the true value precision - how close a set...

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Scientific Measurement

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  • Slide 1
  • Slide 2
  • 1. Yes 2. No
  • Slide 3
  • Accuracy - How close a measurement is to the true value Precision - How close a set of measurements are to one another.
  • Slide 4
  • 1. Accurate 2. Precise 3. Both 4. Neither
  • Slide 5
  • 1. Accurate 2. Precise 3. Both 4. Neither
  • Slide 6
  • 1. Accurate 2. Precise 3. Both 4. Neither
  • Slide 7
  • Slide 8
  • Write each power of ten in standard notation. 10 3 a)30 b)100 c)1000
  • Slide 9
  • Write each power of ten in standard notation. 10 6 a)60 b)1000000 c)10000
  • Slide 10
  • Write each power of ten in standard notation. 10 -2 a).01 b)-20 c)100
  • Slide 11
  • Write each power of ten in standard notation. 10 -4 a)-.0004 b).0004 c)10000
  • Slide 12
  • Setting the Stage There are 325,000 grains of sand in a tub. Write that number in scientific notation.
  • Slide 13
  • What is the exponent to the 10 for 325,000 grains of sand? 1.3 2.4 3.5 4.6 5.-6 6.-5 7.-4
  • Slide 14
  • Definition Scientific notation- is a compact way of writing numbers with absolute values that are very large or very small. Glencoe McGraw-Hill. Math connects cours 3. pages 130-131
  • Slide 15
  • all numbers are expressed as whole numbers between 1 and 9 multiplied by a whole number power of 10. If the absolute value of the original number was between 0 and 1, the exponent is negative. Otherwise, the exponent is positive. Ex. 125 = 1.25 x 10 2 0.00004567 = 4.567 x 10 -5
  • Slide 16
  • 1. -6 2. 6 3. -5 4. 5 5. 4 6. -4
  • Slide 17
  • 1. -6 2. 6 3. -5 4. 5 5. 4 6. -4
  • Slide 18
  • What is 2.85 x 10 4 written in standard form A..000285 B.285 C.28500 D.2850
  • Slide 19
  • What is 3.085 x 10 7 written in standard form A..0000003085 B.30,850,000 C.3085 D.308,500,000
  • Slide 20
  • What is 1.55 x 10 -3 written in standard form A..00155 B.155 C.1550 D..000155
  • Slide 21
  • What is 2.7005 x 10 -2 written in standard form A.270.05 B.27005 C..27005 D..027005
  • Slide 22
  • Write the following numbers in scientific notation: A) 5,000E) 0.0145 B) 34,000F) 0.000238 C) 1,230,000G) 0.0000651 D) 5,050,000,000H) 0.000000673
  • Slide 23
  • Closure / Summary Explain why 32.8 x 10 4 is not correctly written in scientific notation. What does a negative exponent tell you about writing the number in standard form.
  • Slide 24
  • Significant Figures are used to show the accuracy and precision of the instruments used to take the measurement.
  • Slide 25
  • 0 1 0 0 1 1.5
  • Slide 26
  • 0 1 1. 0.55 2. 0.7 3. 0.6 4. 0.8
  • Slide 27
  • 0 1 1. 0.55 2. 0.70 3. 0.67 4. 0.65
  • Slide 28
  • To show how precise the instrument is: Read the measurement to one decimal place what the instrument is marked
  • Slide 29
  • 1. 4.85 2. 7.2 3. 4.3 4. 4.35
  • Slide 30
  • 1. 17.0 2. 16.8 3. 15.18 4. 15.2
  • Slide 31
  • Non-zero digits are always significant 1,2,3,4,5,6,7,8,9 are always significant Rules for Zeros: a) Leading Zeros never count as significant 0.00004560.0032 b) Captive zeros (zeros between non-zero digits) are always significant 10,0340.005008 c) Trailing Zeros are significant ONLY IF there is a decimal in the number. 234,000234,000.00.045600
  • Slide 32
  • If we want to write the number 700 with 3 significant digits we can do so using the following two methods: 700. OR 7.0010 2
  • Slide 33
  • How many significant digits do the following numbers have? A) 20F) 7.00K) 65,060 B) 22.0G) 87,001L) 0.9090 C) 20.1H) 0.00018M) 18.01 D) 56,000I) 0.0109N) 4.3010 4 E) 75,000.J) 570O) 0.0001
  • Slide 34
  • 1. 1 2. 2 3. 3 4. 0
  • Slide 35
  • 1. 0 2. 1 3. 2 4. 3
  • Slide 36
  • 1. 3 2. 1 3. 6 4. 7 1234567891011121314151617181920 2122
  • Slide 37
  • 1. 0 2. 1 3. 2 4. 3 1234567891011121314151617181920 2122
  • Slide 38
  • 1. 2 2. 5 3. 1 4. 3 1234567891011121314151617181920 2122
  • Slide 39
  • 1. 1 2. 2 3. 3 4. 4 1234567891011121314151617181920 2122
  • Slide 40
  • 1. 1 2. 2 3. 3 4. 4 1234567891011121314151617181920 2122
  • Slide 41
  • 1. 5 2. 8 3. 2 4. 4 1234567891011121314151617181920 2122
  • Slide 42
  • 1. 5 2. 8 3. 2 4. 4 1234567891011121314151617181920 2122
  • Slide 43
  • 1. 3 2. 8 3. 4 4. 5 1234567891011121314151617181920 2122
  • Slide 44
  • You and a partner will practice your significant digits. Your job is to come up with a number containing both zeroes and non-zero digits. You will trade boards back and forth on my mark. The partner that gets the correct number of significant digits will get the point. The partner with the most points will win the round. We will do best of 9.
  • Slide 45
  • Count (from left to right) how many significant figures you need. Look at the next number to see if you need to round your last sig. fig. up or down. Round the following to 3 sig. figs 1. 1,344 2. 0.00056784 3. 24,500 4. 12,345 5. 2.45678 x 10 -3
  • Slide 46
  • Slide 47
  • We have two ways of categorizing sig. fig. calculations: A) Addition and Subtraction B) Multiplication, Division, other math
  • Slide 48
  • When we add and subtract we are only worried about the number of decimal places involved in the numbers present. We do not care about the number of actual significant digits. We will always pick the number that has the least decimal places.
  • Slide 49
  • A) 14.0 + 2.45 B) 12 + 7.2 C) 0.00123 + 1.005 D) 100 5.8 E) 2.5 1.25 F) 43.786 32.11
  • Slide 50
  • If we are multiplying, dividing, using exponents, trigonometry, calculus, etc we must use the least number of significant digits of the numbers in the set. For example...
  • Slide 51
  • A) 12 5.00F) 119 / 32 B) 8.45 4.3G) 756.2 / 29.8 C) 0.0125 7.532H) 0.976 / 0.0044 D) 5.6 11.7I ) 981 / 756.23 E) 34.1 0.55J) 43.2 / 12.45
  • Slide 52
  • Density the amount of matter present in a given volume of a substance, the ratio of the mass of an object to its volume. D = mass Volume
  • Slide 53
  • Slide 54
  • Celsius Scale based on the freezing point (0 o C) and boiling point (100 o C) of water. Kelvin Scale based on absolute zero (the temperature at which all motion ceases). 1 degree Kelvin is equal to 1 degree Celsius. Fahrenheit Scale used in US and Great Britain. Degrees are smaller than a Celsius or Kelvin degree.
  • Slide 55
  • Slide 56
  • Kelvin/Celsius K = o C + 273 Fahrenheit/Celsius o F = 1.80( o C) + 32
  • Slide 57
  • Exact Numbers are counting numbers or defined numbers (such as 2.45 cm = 1 in) - never limit the number of significant figures in a calculation.