In the same way that surface colour affects the rate at which objects heat-up and the maximum temperature that they reach (as discussed here) so too will the surface colour affect the rate of cooling. As before, there is a standard experiment that you are expected to know and a typical set of curves that … Continue reading Surface Colour and Cooling
Surface Colour and Heating
Most people say you shouldn't go out on a summer's day wearing black because you will get too hot. It would be much better to wear white as this will keep you cooler. But is that actually true? We can test this idea using two boiling tubes that have been sprayed to have different surface … Continue reading Surface Colour and Heating
Raise your grades!
Back in February I told you about a free online mini-course to help you improve your exam technique over five days. That course is back again so if you missed it the first time, do it now. (Bear in mind that "exam" technique includes tips for improving your answers in tests of all types - … Continue reading Raise your grades!
Speed of Sound in an Iron Bar
Sound travels at different speeds in different materials. We often think only of sound moving through the air (a gas) but in fact it also moves through both liquids and solids. Note that there is a difference between sound moving through a liquid and waves that can be seen on the surface of a liquid. … Continue reading Speed of Sound in an Iron Bar
Speed of Water Waves
For hundreds of years, water waves have been used to understand wave behaviour in general. This is understandable given that water waves are a natural phenomenon that can also be created artificially and studied in the lab. On the simplest level, a stone thrown into the middle of a pond will create waves that extend … Continue reading Speed of Water Waves
Thermal Equilibrium
Any object that has a constant temperature is in a state of thermal equilibrium. This means the rate at which energy is transferred to the object is exactly equal to the rate at which energy is transferred from the object. In the context of electromagnetic radiation, we can state that the rate at which the … Continue reading Thermal Equilibrium
Light and Heat
It is obvious to say that hot objects emit (give off) both visible light (a glow) and heat (that we can feel but not actually see). This is true of bonfires, light-bulbs and even our Sun. The connection between heat and light is taken completely for granted in everyday life: the glow of a hot … Continue reading Light and Heat
Six Impossible Things
Most of the physics you learn at school hasn't changed for hundreds of years. It is important stuff because we know that it works and it underpins a lot of the modern world. But that doesn't mean it is right. This is the point that is made in John Gribbin's new book, Six Impossible Things. … Continue reading Six Impossible Things
Can you beat 49/50?
Doing a test may not be your idea of a cool holiday activity but CGP (the publisher of your revision guide) has just released a series of free online GCSE tests that I highly recommend. You can access the tests at https://www.cgpbooks.co.uk/resources/free-gcse-science-10-minute-tests. On the landing page, select Separate Science then choose Physics. You will have … Continue reading Can you beat 49/50?
Check your Knowledge
The ability to recall key facts and the relationships between those facts is an important part of learning in any context. As we reach the end of the two modules covering Waves and the Electromagnetic Spectrum it is important that you check how much you can remember of the content that has been covered. To … Continue reading Check your Knowledge
Mr Tarrant's physbang 'blog 