Flashcards
Combining Uncertainty
Cards in this deck (12)
- 1When combining uncertainty, the units must be.....The same
- 2For uncertainty of A+B or A-B, we should:Add absolute uncertainties together then recalculate the percentage uncertainty
- 3For uncertainty of AxB or A/B, we should:Add the percentage uncertainty of A to the percentage uncertainty of B
- 4For uncertainty of A^2, we should:Double the percentage uncertainty of A
- 5For uncertainty of A^n, we should:Multiply the percentage uncertainty by n
- 6For uncertainty of A x number (not measured) .....Percentage uncertainty remains constant
- 7For uncertainty of A / number (not measured) .....Percentage uncertainty remains constant
- 8If we measure the thickness of 100 sheets of paper with +/-1mm uncertainty, dividing this by 100 for the thickness of 1 sheet gives the uncertainty:1/100 = +/-0.01mm
- 9A circle has the radius 0.14mm. Find : 1. The area 2. The percentage uncertainty 3. the absolute uncertainty0.14mm = 1.4x10^-4m.
% uncertainty of r: 0.01/0.14 x 100 = 7.1%
1. Area = π(1.4x10^-4)^2 = 6.2x10^-8 m^2
2. % uncertainty in r^2: 7.1 x 2 = 14.2%
3. (6.2x10^-8)x14/100 = 8.69x10^-9 m^2
Therefore area =
6.2x10^-8 m^2 +/- 8.69x10^-9 m^2 - 10How do we calculate the range?|Biggest - Smallest|
- 11When we repeat readings / judgments, the absolute uncertainty can be calculated by.....Halving the range
- 12When calculating the range, we should ignore.....Anomalous results