1. Measurement Errors

2. Digital scale

3. Addition and Subtraction Measurement Errors Δy = the absolute error in y Δa = the absolute error in a Δb = the absolute error in b Example:

4. Multiplication and Division Measurement Errors

5. Example:

6. Practice Problem: Calculate the surface area of the following rectangular prism. 8.4cm ±.1cm 4.5cm ±.1cm 3.2cm ±.1cm

7. Order of Magnitude – The power of ten closest to a given number. Range of Magnitudes of the Universe http://micro.magnet.fsu.edu/primer/java/scienceopticsu/ powersof10/

8. Examples: 7.0 2.0 10000 3.16 9.11 x 10 -31 365 4.24 x 10 -13 4,200,000

9. Estimate the number of heartbeats in an average human lifetime.

10. Estimate the volume of our body in cm 3. The mass of your backpack that contains your school materials in grams.

11. Fundamental of the International System (IS): QuantitySI UnitSI Symbol lengthmeterm masskilogramkg timeseconds Electric currentAmpereA temperatureKelvinK Mattermolemol Luminous intensitycandelacd

12. Random and Systematic Errors Systematic errors push the results in the same direction. They are a system or instrument error. Examples: A scale that has not been zeroed. A clock that runs slow or fast. Parallax error Systematic errors present graphically as an unexpected vertical intercept or a slope which is significant different from the expected value.

13. Random errors are scattered about the accepted values due to variations in the performance of the instrument and operator. Examples: Reading errors Temperature variations Timing errors Random errors present graphically as scattering of data about the expected graph.

14. Precision and accuracy