1/6/11

Post date: Jan 05, 2011 9:25:33 PM

  • Bell ringer: What is scientific notation and when is it useful?

  • Purchase lab manuals ($1.25)

  • Turn in lab safety contracts, syllabus agreements

  • Quiz tomorrow:

    • 1. Scientific knowledge / ideas

    • 2. Putting numbers into and out of scientific notation

    • 3. Arithmetic with scientific notation.

  • Measurement notes

    • Measurements ...

          • Are a form of observation

          • May provide evidence to help us formulate a theory

          • Accurate measurements help us make more accurate theories

        • Are based in time, distance, and mass

      • The SI system (the metric system)

          • Used everywhere except USA and Australia (and sort of Britain)

          • Used in SCIENCE

          • Uses prefixes to make larger or smaller increments

          • Time (second) - related to frequency of radiation from Cs-133

          • Distance (meter) - distance traveled by light in a vaccuum in 1/ (299,792,458) seconds

        • Mass (kilogram) - mass of a platinum-iridium rod kept near Paris

      • Distances

          • How far between two points

          • Basic unit is the meter (m)

          • For small measurements, we use the centimeter (1/100th of a meter) or the millimeter (1/1000th of a meter)

          • For large measurements, we use the kilometer (1000 meters)

        • To measure distance, we can use meter sticks and rulers

    • Work time for measurement lab (due Friday)

      • Scientific notation notes

      • Used to express very large or very small numbers

      • General format is M x 10^n

          • M is the non-zero numbers at the left side of a very large or small number. M is always a number with only one digit to the left of the decimal

          • n tells us how far to move the decimal place (positive means right, negative means left)

          • e.g. 4.5 x 10^3 is the same as 4500 (decimal in 4.5 was moved to the right 3 places)

          • e.g. 6.8 x 10^-3 is the same as 0.0068 (decimal in 6.8 was moved to the left 3 places)

Read "Scientific Notation" on pages 15-16

Do Page 16: 1-3, 6-7, 9-10 for practice

Practice problem recommendations:

    • Write problem, work, and answer

    • Check answer only AFTER completing the problem

    • Cross out, don't erase

    • Write yourself tips as you work

    • Ask yourself, "what am I likely to forget between now and the test and/or final exam?"