with mr mackenzie
There’s a nice item on quantum tunnelling on the BBC News site.
Scientists at Peratech have developed “spikey” particles for use in the touchscreen of smartphones. The breakthrough is that the quantum tunneling effect means that the screen is pressure sensitive.
I found this video on quantum tunneling on youtube.
I found this video on youtube. It is a good demonstration of electrons behaving like waves or particles, depending on their energy. Can you explain why the electron energy is important here?
There is a second video explaining how the electrons are produced if you are interested. Watch it here.
It’s a few months since we looked at centripetal acceleration in class but I thought I would share this article I found. I wonder how many people would dare to “co-write” a physics paper with Isaac Newton? The article is worth a read and I have attached a download link below.
While we’re talking about centripetal acceleration, Rhett Allain’s blog post that led me to the article is also very interesting.
We’ve just started to look at the parts of unit 1 we left behind in November. The first of these is Quantum Physics. It’s a strange topic and you might want to stick your head in the sand of classical physics and seek refuge in waves. Luckily, Prof. Chad Orzel has come to our rescue with a blog post called Four things everyone should know about Quantum Physics.
Prof. Orzel is also the (co)author of a book called How to teach Physics to your dog. I’ve not bought it yet but the free download of chapter one (use the link below) mentions some of the ideas we have looked at already and mentions some names that should be familiar by now: Einstein, Planck, de Broglie (is that picture of de Broglie wrong, looks like a young Einstein to me?) and Millikan.
Have a read of the introductory chapter and share it with you dog. The interview is good too.
Here are the links to past papers on the SQA site. If you need an older paper, please come and ask.
On Monday, we discussed Millikan’s famous experiment to determine the charge on an electron. Some of the slides I used during the lesson were taken from a site created by Joe Rowing, who teaches physics in Brighton. You can download the full powerpoint file and handout sheets here.
We performed a small experiment to show how Millikan was able to calculate the charge due to a single electron. Balloons filled with different numbers of beads replaced the charged oil drops and allowed us to simulate Millikan’s method using an electronic balance. The mass of a single bead at 0.22g – congratulations to those of you who were able to reach this value!
If you look at the slides on the site I linked to above, you will find a description of the experiment I based this on. Mr Rowing used sweets instead of beads.
We started unit 2 of the AH course today and I mentioned that it was Benjamin Franklin who introduced the terms positive and negative to describe electrical charges. Our friends at xkcd have a cartoon about it.
The Astronomer Royal for Scotland, Prof. John Brown, will be in Thurso on Tuesday 10th November. He’s giving a talk on black holes at the Pentland Hotel as the guest of the local Institute of Mechanical Engineers. We’ve just started to look at this topic in class and I hope some of you will be able to come along. See the attached poster for more details.
Here are the diagrams you will need for your LO3 report. Cick on each link and then save the large image that opens up. You can rezise them once they have been imported into your report.
A cartoon to celebrate reaching centripetal force. Enjoy.
