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Edexcel A2 Physics Unit 6 help

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mustafa09:
How can i find the uncertainty from a graph.....i searched on the internet and i had to draw error bars...what are error bars???

Deadly_king:

--- Quote from: mustafa09 on May 18, 2012, 10:39:09 am ---How can i find the uncertainty from a graph.....i searched on the internet and i had to draw error bars...what are error bars???

--- End quote ---

Error bars tell you how inaccurate your data point is. The larger the error bars, the less accurate the measurement.

Imagine you've got a ruler and were measuring the length of a box. Up close, you can measure it pretty accurately, giving you, say, 1.33 m +/- 0.01. Your error is very small because you had a good way to measure it. But if you had to stand across the room and try to estimate it from there, you might have to say 1.0 m +/- 0.5; or much larger error since you don't have good measuring technique.

Example : Let's say you gotta plot the point 5 +/- 0.5 m on a graph
So you plot the point 5 and the draw a line from 4.5 to 5.5 while passing through 5, so as to represent the errors. The line you just drew is called an error bar ;)

Here is something which might help :)

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