Combining Uncertainties - WORKED EXAMPLE - A Level Physics

This is a worked example on combining uncertainties for A Level Physics. I record some data, calculate the various percentage uncertainties, then combine these and show you how to find the total uncertainty in the volume of a rod.

Thanks for watching,

Lewis

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[livelygoats]

So for measurements with multiple readings, it doesn't matter what the uncertainty on the measuring device is as you will only use the range and the mean anyway?

[FlixRacing]

THANK YOU! EXAM TOMORROW! Good luck everyone!

[usayededu]

sir love your videos. currently preparing for my As exams in coming may.
Pray I do well.

[geoffphillips]

Great help, thanks. Never as well explained in books as your vid! 😊

[hiper_tops]

how do you find %uncertainty of y if y=a+b? where a and b have different units like meters and seconds? Could you even ever have that scenario?

[Darkknight]

If the uncertainty in a diameter is .10mm then what is the uncertainty in the radius?

[oliverhume]

But for the diameter don't you use the resolution not half the range as the resolution is bigger

[simondavid]

1. The uncertainty of an individual measurement of the diameter should be 0.005 mm as a micrometer is an analogue device.
2. When you combine the uncertainties for the 3 measurements, you got a value lower than the uncertainty of the individual measurement, which is very wrong. To calculate the range, you should have taken the lowest possible and the highest possible values, which then would include the individual uncertainties.

[mrboyban]

Completely pointless to have that on the exam!

[MrMas]

For the individual uncertainties of the diameter, shouldn't it be plus or minus 0.005mm (as that is half the smallest division)?

[pokrui]

Tips for students: check your exam board and syllabus