Combining Uncertainties - A Level Physics

You can calculate the percentage uncertainty in the various measured values when you complete practical work for A Level Physics. Combining uncertainties needs extra care. This video shows how to combine uncertainties (adding uncertainties together) to give the final uncertainty in a calculated value.

Thanks for watching,

Lewis

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[jemimaify]

You’re the only physics guy on YouTube who goes quickly and precisely enough for me, I put everyone else on x2 speed, thank you!!

[tashreeqa_ek]

It's an hour before my exam and suddenly I feel like I forgot everything. Thank you soooo much! You're a lifesaver

[arjunradia]

Have my first physics exam later today and this was a topic I didn't understand. Cheers for putting it in such a clear way

[kobedunlop]

thankyou so much last minute procrastinators worship you

[hemanawesoke]

Thanks, couldnt find this online, everyone was just talking about how to find the percentage and not how to find overall

[devonjay]

THANKS KING, i have my last exam in two days, NEEDED this

[TheObloINATOR]

best channel on youtube man i watch these vids for fun most nights

[slopherones]

Cheers Sir Extremely easy to understand video as a yr 11 student who just finished his exams and is revising for the ocr a physics syllabus a level these videos are really helping me to solidify concepts I haven't encountered at gcse

[scottjulien]

Excellent. Thank you for posting this. Very helpful.

[bendewes]

If you are square rooting a value, do you half the percentage uncertainty?

[XTRA_THICC]

does this also apply to absolute uncertainties, not just percentage?

[ameliajones]

What about if you are adding or subtracting values? Also yes what do you do if you are square rooting a value?

[chriswesley]

This is a very clear explanation of how to get the right answer, but it offers nothing whatsoever by way of an explanation of WHY.
This is why I struggle so much at schoole - I was a screaming BUT WHY??!!

[kr-sdni]

what kind of pen is that? writes really nice and dries quite fast

[julianperry]

Very clear video. Thank you. I’d like to ask how you combine errors when you’re not sure of the relationship between the measured value and the various factors that effect it? Do you just quote the uncertainty in the measured value?

[chunt]

what about adding values with uncertainties e.g. (a+/- x) + (b+/-y) = ?

[leonardo.q]

What if the formula is a+b, whats the uncertainty?

[duncanmullaney]

do you not calculate the maximum final density value (i.e. put extreme error values in that would maximize numerator and minimize denominator) call this A, then calculate the minimum final density value (i.e. put extreme error values in that would then minimize numerator and maximize denominator) call this B, then quote the final error in the final term as plus/minus half the range between A and B?

[joebloor]

Does this only work with % uncertainties?

[tomu]

Hey! How would you combine unceratinties when multiplying data with an uncertainty by a constant?