The previous post (Experimental Errors, https://physbang.com/2023/11/12/experimental-errors/) ended with an invitation to "consider whether there are any other, previously unidentified, sources of uncertainty" in the method used to derive the specific heat capacity of an iron block. As it happens, there are (at least) three possibilities that weren't covered in the original article. Firstly, there is … Continue reading Experimental Errors (part 2)
Experimental errors
Experiments are often used to confirm (or, more usefully, refute) particular ideas but their impact is limited by measurement errors that can compromise the results. The obvious answer is to reduce the uncertainties as much as possible but what do you do if this causes the result to move further away from the expected value? … Continue reading Experimental errors
Common Mistakes (part 2)
This is the second set of tips for avoiding some of the mistakes made by students sitting AQA GCSE Trilogy science papers. It is based on the exam board's advice, which can be downloaded from https://filestore.aqa.org.uk/resources/science/AQA-GCSE-SCI-TG-MISUNDERSTANDINGS.PDF, together with observations and explanations of my own. To read the first part of this summary, see https://physbang.com/2023/05/01/common-mistakes-part-1/. 7. … Continue reading Common Mistakes (part 2)
Command Words
Examination questions always include a word that specifies what you must do to get full marks. These are the command words and they are important because you must match your answer to what they are expecting. It is easy to lose marks by not paying careful attention to the command word so here are some … Continue reading Command Words
Standard Form
Every GCSE physics paper normally has at least one question with a mark for the correct interpretation or expression of numbers in standard form. This is a basic skill that is taught as part of GCSE mathematics courses but it holds a great deal of power for scientific calculations that is rarely mentioned at this … Continue reading Standard Form
Congratulations
The results are in and, overall, the AQA Trilogy course has been very successful. I have heard of some great individual results and I've been delighted to shake hands with some of you. I also know there have been some slight disappointments but that is the way things are: we live and learn (please never … Continue reading Congratulations
Revising Atomic Structure
Tucked away inside a website of astronomy resources I have just found a brilliant little tool for revising atomic structure, which is required knowledge for AQA Trilogy (and other) GCSE examinations in both physics and chemistry. You can find it at https://astro.unl.edu/newRTs/nuclei/. The assessment is a two-part, drag-and-drop ranking exercise where you have to rearrange … Continue reading Revising Atomic Structure
AQA Trilogy – Summer Exams 2022 (revision links)
AQA recently issued guidance about the topics that will be included, and excluded, for this year's GCSE papers (available here). I've gone through AQA's document and mapped the physics topics for Trilogy to revision resources provided by BBC Bitesize: the links are on a dedicate webpage, at https://start.me/p/2px9qe/aqa-trilogy-revision-summer-2022 (see screen-grab below). This page is not … Continue reading AQA Trilogy – Summer Exams 2022 (revision links)
Determination of ‘little-g’
One of my favourite experiments in GCSE physics is a practical that seems to have fallen from favour in recent years – but it’s still worth exploring. The experiment involves using a ticker-timer to make dots at regular time intervals (0.02 s apart) on a strip of tape that is attached to a moving object. … Continue reading Determination of ‘little-g’
Acceleration and Distance
To find acceleration without measuring time, we can use a combination of the object's mean speed and distance-moved as a substitute for time. We already know that speed is calculated as distance divided by time, so we can rearrange this equation to calculate time as distance divided by speed. Of course, the speed of an … Continue reading Acceleration and Distance
Mr Tarrant's physbang 'blog 