Successfully reported this slideshow.

Ppt accuracy precisionsigfigs 2014 fridays notes

8

Share

Upcoming SlideShare
Accuracy precision errors
Accuracy precision errors
Loading in …3
×
1 of 18
1 of 18

More Related Content

Related Books

Free with a 14 day trial from Scribd

See all

Related Audiobooks

Free with a 14 day trial from Scribd

See all

Ppt accuracy precisionsigfigs 2014 fridays notes

  1. 1. Accuracy & Precision Two important points in measurement (We start the year with a math unit then we will study atoms, ions, and the periodic table.)
  2. 2. Accuracy and Precision At the conclusion of our time together, you should be able to: 1. Explain the difference between the accuracy and precision 2. Give examples of accuracy and precision This information is from Chapter 3.1
  3. 3. Accuracy  Accuracy = the extent to which a measured value agrees with a standard value Accuracy of a device must be checked Does it read a proper accepted value?  Beware of Parallax – the apparent shift in position when viewed at a different angle.
  4. 4. Graduated Cylinder – Meniscus and Parallax
  5. 5. Example: Accuracy  Who is more accurate when measuring a book that has a true length of 17.0 cm? Susan: 17.0 cm, 16.0 cm, 18.0 cm, 15.0 cm Amy: 15.5 cm, 15.0 cm, 15.2 cm, 15.3 cm
  6. 6. Murphy's Laws of Science and Technology Technology is dominated by those who manage what they do not understand.
  7. 7. Precision  Precision = the degree of exactness of a measurement that is repeatedly recorded.  Which set is more precise? 18.2 , 18.4 , 18.35 17.9 , 18.3 , 18.85 16.8 , 17.2 , 19.44
  8. 8. Example: Precision Who is more precise when measuring the same 17.0 cm book? Susan: 17.0 cm, 16.0 cm, 18.0 cm, 15.0 cm Amy: 15.5 cm, 15.0 cm, 15.2 cm, 15.3 cm
  9. 9. Accuracy vs. Precision High Accuracy High Precision High Precision Low Accuracy
  10. 10. CCaann yyoouu hhiitt tthhee bbuullll''ss--eeyyee?? TThhrreeee ttaarrggeettss wwiitthh tthhrreeee aarrrroowwss eeaacchh ttoo sshhoooott.. Both accurate and precise Precise but not accurate Neither accurate nor precise HHooww ddoo tthheeyy ccoommppaarree?? CCaann yyoouu ddeeffiinnee aaccccuurraaccyy vvss.. pprreecciissiioonn??
  11. 11. Why Is There Uncertainty? • Measurements are performed with instruments, and no instrument can read to an infinite number of decimal places •Which of the instruments below has the greatest uncertainty in measurement?
  12. 12. The Scientific Method begins with Questions about the World Around You. Ever Wonder Why?... Braille dots are on the keypads of drive-up ATM's?
  13. 13. Accuracy and Precision Let’s see if you can: 1. Explain the difference between the accuracy and precision 2. Give examples of accuracy and precision
  14. 14. Exit Quiz: Evaluate whether the following are precise, accurate or both. Low Accuracy Low Precision Low Accuracy High Precision High Accuracy High Precision
  15. 15. Significant Figures In Measurements
  16. 16. Significant Figures At the conclusion of our time together, you should be able to: 1. Explain what significant figures are in a measurement 2. Determine the number of significant figures in any measurement
  17. 17. Significant Figures The significant figures in a measurement include all of the digits that are known, plus one last digit that is estimated. The numbers reported in a measurement are limited by the measuring tool.

×