My Motivational Speech

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(No Transcript)
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My Motivational Speech

• Focus on learning, not on grades. Learning
  brings success, and life-long learning brings
  life-long success.
• If I offered to hire you for one month (30 days
  straight!) and offered to pay you 1,000,000 or 1
  penny on the first day, but double your wages
  each day, which would you accept?
• If you take the penny, you make over 5 million
  dollars on the 30th day (over 10 million for the
  month)
• Its how you grow thats important, not how much
  you start with!

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Chapter 01

• Measurements

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Units

• For us to communicate how much something is, we
  must use units.
• What if I were to offer a job to you that pays an
  annual salary of 60,000 per year? Would you
  accept the job?
• Three of the fundamental units used in the SI
  system (SI is the most common system of units
  used in science)
• unit of mass, kilogram (kg)
• unit of distance, meter (m)
• unit of time, second (s)

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Unit Prefixes
prefix meaning power of 10
micro one-millionth 10-6 1/1,000,000
milli one-thousandth 10-3 1/1000
centi one-hundredth 10-2 1/100
kilo one thousand 103 1000
mega one million 106 1,000,000
giga one billion 109 1,000,000,000
tera one trillion 1012 1,000,000,000,000
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Scientific Notation
There is an easier way to express numbers so that
we dont have to count all those digits and
commas.
9850 kg 9.85 x 103 kg 9.85 x 106 g 299,792,
458 m/s 2.99792458 x 108 m/s 384,403 km
3.84403 x 105 km 3.84403 x 108 m
The mass of the earth is 5.97 x 1024 kg. Do you
really want to write that number without using
scientific notation?
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Poll

• The width of a DNA molecule is about
  0.0000000002 m. In scientific notation, this is
• 2 x 10-8 m
• 2 x 108 m
• 2 x 10-10 m
• 2 x 1010 m
• None of the above.

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Poll

• Earths equatorial radius is 6378 km. What is
  this number written in scientific notation?
• 6.378 x 101 m
• 6.378 x 10-3 m
• 6.378 x 102 m
• 6.378 x 103 m
• None of the above

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Unit Conversion

• Write your conversion factor as a ratio equal to
  1.
• Multiply the quantity by 1 (the conversion
  factor) so that units cancel as needed.
• Multiply by 1 as many times as needed.

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Poll

• A football field is 100 yd long. What is its
  length in meters?
• 100 m
• 109 m
• 9 m
• 82 m
• 91 m

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Poll

• My office has a volume of 1000 ft3. What is its
  volume in m3?
• 394 ft3
• 305 m3
• 0.3 m3
• 28 m3
• None of the above.

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Poll

• Suppose that you burn 280 calories of energy
  while working out for 20 minutes on an elliptical
  machine in the gym. How many joules of energy did
  you burn?
• 1170 J
• 67 J
• 280 J
• 5600 J
• None of the above

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Poll

• By measuring a persons density, one can
  calculate his body fat. If a person has a
  density of 1.05 g/cm3, what is his density in
  kg/m3?
• 1.05 x 103 kg/m3
• 1.05 x 106 kg/m3
• 1.05 x 102 kg/m3
• 1.05 x 104 kg/m3
• 1.05 x 109 kg/m3

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Proportionality

• Sometimes we want to know how one variable
  depends on another variable.
• For example, for a circleso doubling the
  radius increases the circumference by a factor of
  2.
• When one variable is directly proportional to
  another variable, we write

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Poll

• The volume of a cylinder is V pR2h. If you
  double the radius of the cylinder, how much more
  volume will it have?
• Itll have the same volume.
• 2 times more volume.
• 4 times more volume
• 8 times more volume
• Half as much volume.