7 Uncertainty Lab Notes 1 25 3 0

7 Uncertainty Lab Notes

1. 25. 3 0. 2 mm less precise more uncertainty The measurement is between 25. 1 mm and 25. 5 mm 25. 1 2. 25. 35 0. 01 mm 25. 5 more precise less uncertainty The measurement is between 25. 34 mm and 25. 36 mm 25. 34 25. 35 25. 36

Is there a difference between the following measurements? Uncertain digit Range Precision Uncertainty 5 m 5. 000 m 4 -6 4. 9 - 5. 1 4. 99 - 5. 01 4. 999 - 5. 001 low high low

Reading a Micrometer All micrometer units are in mm. Fixed Scale Rotating Scale Measurement 5. 00 mm 0. 21 mm 5. 21 mm

Reading a Micrometer All micrometer units are in mm. Fixed Scale Rotating Scale Measurement 10. 50 mm 0. 31 mm 10. 81 mm

Reading a Vernier Scale All units are in mm. What lines up the best with a line above? 0. 05 Fixed Scale Vernier Scale Measurement 12. 00 mm 0. 05 mm 12. 05 mm

Reading a Vernier Scale Fixed Scale Vernier Scale Measurement 15. 00 mm 0. 60 mm 15. 60 mm All units are in mm What lines up the best with a line above? 0. 60

Reading a Vernier Scale All units are in mm. Fixed Scale 8. 00 mm Vernier Scale 0. 50 mm Measurement 8. 50 mm 0. 50

Uncertainty and Significant Figures 1. 37 0. 02 v Uncertainty is a one digit number that indicates the range in which the accepted or true value most likely lies- 95%. Uncertainty is the natural variation that is inherent in all measurement. All measured values, those with units, have uncertainty.

The last digit of the measured value is the only digit that contains uncertainty and is in the same decimal place as the uncertainty. Average 1. 37 0. 02 v Uncertainty The uncertainty is only one digit. The unit goes last. Unit

Good Accuracy- how close to the accepted value the measurement is. xxxxx

Good Precision Poor Accuracy xxxxx

Poor Precision Poor Accuracy x x x

Homework Lab Conclusion and Questions Do Ionic Formulas Quiz