Having previously discussed micrometers as instruments that some people find tricky to read (see https://physbang.com/2025/04/09/how-to-read-a-micrometer/) we now come to the instrument that many people find even more difficult; Vernier callipers. Whereas micrometers are mostly used for measuring thicknesses between flat surfaces, callipers are better when the surfaces are curved. In particular, callipers are commonly used … Continue reading How to read Vernier callipers
Random and Systematic Errors
Two previous posts covered uncertainties in the context of thermal energy transfers but now we need to consider random and systematic errors as they apply more generally in the current AQA A-Level Physics course. NOTE: The AQA A-Level Physics syllabus takes a simplified approach to uncertainties so if you are doing independent revision you may … Continue reading Random and Systematic Errors
How to read a micrometer
Being able to take measurements using common items of instrumentation is an expected skill for A-Level Physics and can be tested in examinations using diagrams or photographs. This post is the first in a short series that will look at measurement skills, starting with a piece of equipment that often causes difficulties; the micrometer. To … Continue reading How to read a micrometer
Paper 3a, Q3 walk-through
This post completes an explanation given to my current Y13 students, which was unfinished at the end of our lesson. It relates to the second half of Q3 in Paper 3a for the AQA A-Level Physics examination of June 2023. You can download a copy of the complete paper here. To solve Q3.4 you must … Continue reading Paper 3a, Q3 walk-through
What is Spin?
Spin, when applied to fundamental particles, is a property rather than a description. The basic components of matter are not tiny spinning tops, like coins that are stood on edge then flicked on opposite sides to make them rotate. Instead, spin is a physical property that can be demonstrated and also a numerical value that … Continue reading What is Spin?
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