Can %age uncertainty in value ever be greater than 100?

In summary, the conversation discusses an experiment where the uncertainty of the majority of students was greater than 100%. The topic of drawing a graph of a Hooke's Law experiment while in an off road vehicle is brought up, and it is suggested that taking enough readings could lead to a more accurate result. The question is raised about why the uncertainty cannot be greater than 100% and what would happen if the expected result of an experiment is zero.
  • #1
Asad Raza
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We were given an experiment in which the %age uncertainty of majority of students happened to be greater than 100?
 
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  • #2
Sit in the seat of an off road vehicle and try to draw a graph of a Hooke's Law experiment whilst on the move. How bad could it get?
 
  • #3
Never did that. You tried it? What was the uncertainty?
 
  • #4
I never did it but can't you imagine the sort of results?
If you did the experiment for long enough and took enough readings, you could end up with a pretty good value for the spring constant. Averaging (I.e.data filtering) can be a powerful tool.
 
  • #5
Why the uncertainty can not be greater than 100%. Prove it logically?
 
  • #6
Asad Raza said:
Why the uncertainty can not be greater than 100%. Prove it logically?
What if the expected result in an experiment is zero? What is the percent uncertainty then?
 
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  • #7
Asad Raza said:
We were given an experiment in which the %age uncertainty of majority of students happened to be greater than 100?
I don't understand why you are asking the question. You already have data in front of you where the relative uncertainty is greater than 100%, so clearly using that data you can demonstrate that the relative uncertainty can be greater than 100%.

Since you already have data showing that it can be greater than 100%, what is your real question?
 
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1. Can the percentage uncertainty in a measurement ever be greater than 100%?

Yes, the percentage uncertainty can be greater than 100% if the uncertainty in the measurement is larger than the measured value itself. This can happen, for example, when the measurement is very small or when there is a large amount of error in the measurement process.

2. Is it possible for the percentage uncertainty to be negative?

No, the percentage uncertainty cannot be negative. This is because uncertainty is a measure of the potential error or deviation in a measurement, and it cannot be negative. If the uncertainty is calculated to be negative, it is likely that there was an error in the measurement or calculation process.

3. How does the percentage uncertainty affect the accuracy of a measurement?

The percentage uncertainty represents the potential error or deviation in a measurement. A larger percentage uncertainty means that there is a higher chance that the measured value is further from the true value. Therefore, a higher percentage uncertainty can decrease the accuracy of a measurement.

4. Is there a limit to how high the percentage uncertainty can be?

No, there is no limit to how high the percentage uncertainty can be. However, if the uncertainty is larger than the measured value, the percentage uncertainty will be greater than 100%. In most cases, a percentage uncertainty of 100% or higher indicates a significant amount of error in the measurement.

5. How can one reduce the percentage uncertainty in a measurement?

The percentage uncertainty can be reduced by improving the precision and accuracy of the measurement process. This can be achieved by using more precise measuring instruments, taking multiple measurements, and minimizing sources of error. The percentage uncertainty can also be reduced by increasing the magnitude of the measured value, as the uncertainty will become a smaller proportion of the overall value.

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