Haborix said:My first thought is to consider significant figures. If you were given a value of 10, would you think it's reasonable to have an uncertainty of +/- 0.1? Probably not, because the output you have is not given to any decimal places. So in this case where we have 502.4g we should ask how exact can we get before we reach the limit of the measurement.
-Eric
aborder said:Homework Statement
If an electronic scale reads 502.4 g, what is the absolute uncertainty in the mass reading.
Homework Equations
Not sure
The Attempt at a Solution
Not a clue, it seems that there isn't enough information given. How am I supposed to figure out the absolute uncertainty if this is all that is given?
Phrak said:It's a lousy question and your text should be burned in an effort to the improvement the human condition.
However
It seems we are supposed to assume the measuring electronics deliver 100% accuracy to the display.
If the actual mass were 502.351 g what would the meter read?
If the actual mass were 502.449 g what would the meter read?
PeterO said:I think all figure are taken as =- 1/2 of the last digit - unless stated as bigger.
So 502.4 =-0.05
aborder said:Wouldn't it also be + 0.05 as well if the meter rounds to the nearest tenth? I guess we really don't know since there isn't any additional information provided.
aborder said:I suppose that it would read 502.4 because it rounds to the nearest tenth. I guess we assume that when only the tenths place is given. The thing is, how do I know what to assume when this isn't discussed in the text.
phrak said:given that I've correctly read between the lines of your text, what do you get for the absolute error?
PeterO said:Look at the keyboard ... I was too brief with the shift key so got = instead of +
PeterO said:Look at the keyboard ... I was too brief with the shift key so got = instead of +
Phrak said:That's a good trick. How do you typo "+/-" into "="? The fingers must by flying.
Absolute uncertainty refers to the range of possible values that a measurement or calculation could have, taking into account all sources of error and the precision of the measuring instrument.
Absolute uncertainty is a measure of the total uncertainty in a measurement or calculation, whereas relative uncertainty is a ratio of the absolute uncertainty to the measured quantity. Absolute uncertainty takes into account the precision of the measuring instrument, while relative uncertainty does not.
The main factors that contribute to absolute uncertainty are the accuracy and precision of the measuring instrument, the skill and technique of the person making the measurement, and any external factors that may affect the measurement, such as environmental conditions or human error.
Absolute uncertainty is typically calculated by taking the difference between the highest and lowest possible values of a measurement or calculation, divided by two. This represents the range of possible values that the measurement could have within the stated uncertainty.
Absolute uncertainty is important because it allows us to understand and communicate the accuracy and reliability of a measurement or calculation. It also helps us to evaluate the significance of our results and determine if they are precise enough for the intended use or application.