Summary
Summary AQA A-level Physics: Section 1 - Measurements and their Errors
AQA Physics: Section 1 - Measurements and their Errors Everything here is covered and teaches you how to use your practical skills for paper 3.
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
Seller
Follow
Content preview
Introduction to Practical Work and MathematicsUncertainties
Absolute uncertainty = the uncertainty of a measurement given as a fixed quantity.
Fractional uncertainty = uncertainty given as a fraction.
Percentage uncertainty = the uncertainty given as a percentage of the measurement.
You can decrease the uncertainty % by increasing the value of what you are
measuring.
E.g. You measure 10mm with a mm ruler and get an uncertainty of 10% but if you
measured a length of 20mm it would be an uncertainty of 5%.
The uncertainty on a mean of repeated results is equal to half the range of the
results.
Raising to a power - MULTIPLY PERCENTAGE UNCERTAINTY BY POWER
Adding or subtracting
1. Subtract the lengths without the uncertainties.
2. Then find the total uncertainty by adding the individual absolute uncertainties.
Multiplying or dividing
1. First calculate the value without the uncertainty.
2. Then calculate the percentage of all the uncertainties and add them together.
3. Then times the value without uncertainty with the percentage to find the
uncertainty.
Uncertainties and graphs
Uncertainties are shown as error bars on graphs,
e.g. if the uncertainty is 5mm then have 5 squares of error bar on either side of the
point A line of best fit on a graph should go through all error bars (excluding
anomalous points).
The uncertainty in a gradient can be found by lines of best and worst fit:
Or if there is a y-intercept:
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller ttom. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £3.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67474 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now