Standing waves on a spring

Posted: October 29, 2014 in Institute of Physics
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You might have seen/done this one before, but the teachers I was showing it to found it quite useful, so I thought I would post it on talkphysics. The nodes and anti-nodes are a lot clearer when the amplitude of the oscialltions is higher, but I was told the signal generator broke the previous vibrator when set too high, so I was a bit cautious with this one.

There are several teaching and learning points with this demo. For example, you could get the students to calculate the speed of the wave along the spring, as we know the frequency from the signal generator and can measure the wavelength (for example by measuring the length of the stretched spring with a ruler).

Once we know the speed of the wave, we could ask the students to predict the next frequency in which a standing wave will form.

What else would you use this demonstration for? What other questions would/could you ask?

Teaching Forces on a trampoline!

Posted: June 4, 2014 in Thoughts and ideas
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It can be tricky to find good examples to show how forces add up to give a resultant force. In particular, sum of vector forces in AS Physics is something that takes practice in order for students to grasp. So, when one of my boys enjoyed a ride on one of those trampolines where they strap you to two elastic ropes to make you jump very high I thought it would be useful to share this photo with you. The tensions from the two ropes pull him at the same angle on either side, but he jumps up vertically. Why does this happen? You can ask students. Then force arrows could be drawn and look at their vertical and horizontal components to see that the horizontal components are balanced and the vertical components add up, etc…

What other useful concrete examples do you use with your students?

Sorry the photo got uploaded on its side instead of the right way up, but you should be able to easily rotate it on a PPT presentation, or you could mess with you students and tell them it was taken at the Equator 😀 and see what they say!

I have always found it is quite hard to show the path of the current in a bridge rectifier to A-level students using diodes alone. The diodes are tiny, for a start, and you end up following the wire with your finger around, but students seem to get lost in the process. I still introduce the rectifier using diodes and one thing I show them is that even using a DC voltmeter doesn’t change the sign. This is convincing for some, but it is still nice to be able to give further proof of what’s going on.

The diagram might also help, because it is easier to follow the path around.

However, I have started building rectifiers with LEDs alongside the diode version and it works a treat. The first thing I show them is the circuit on DC current. Only two of the four LED light up, so I can ask “What would happen, if I reverse the polarity?” They now seem to get it and they often answer correctly that the other two LED will light up. I change the polarity several times to simulate the two half-waves, as in the images below.

Then, I get the spinning wheel we use to observe ripples in the ripple tank (the one with gaps, I can’t remember the name) and put the LED rectifier on AC. The result can be seen in the video below.

Anyone who insists technology is disempowering has probably not come across really young learners interacting with it. Today I was reminded about how intuitive, engaging and formative technologies like the iPad really are.

I want to call Nonna!

My 2 year old boy, Martino, felt like talking to Nonna (grandma in Italian). I say talking, but, although he can say quite a few words, he hasn’t learnt to say many sentences yet. What he has learnt to do, and very quickly, is to use an iPad. In fact, he’s so good at it that today he ran in the kitchen, took the iPad Mini and came back to the sofa looking pleased with himself. Then, he turned it on, swiped to access the apps, found FaceTime inside a folder and called my mum from the recent calls. When Matteo (my eldest) heard the ringing sound of FaceTime he asked Martino, if he was calling Nonna. “Sí, Sí!” answered Martino.

Needless to say that this unexpected call made my mum’s day, but what I’ve witnessed today, and many other times since Martino was one and a half, is something that made me think deeply about the power of technology.

Our learners are deeply engaged with technology, they grow surrounded by it and naturally embrace it as part of their learning. I believe it is essential we engage our students with technology to harness this enthusiasm our young people show for it. I heard of many primary and secondary schools that began to use iPads when they noticed their youngest learners kept touching the screen of PCs and laptops the first time they used them. iPads, smartphones and tablets are engaging and an integral part of many learners’ every day routines. They are drawn to them and naturally interact with such devices with great interest and proficiency, so using them in the classroom seems to me to be a logical way to engage children in their learning. This will make schooling more fun, but that should never be the driver for integrating technology in the classroom! iPads and other technologies open ways to redefine pedagogy and learning experiences. They empower learners and teachers, so that students become more independent and creators of knowledge, rather than simply consumers of knowledge. Let’s embrace technology for the right reasons and not thinking that the kit will solve all the teaching and learning challenges in our schools.

There are many ways to use technology creatively and innovatively to enrich our learning environments and much can be learnt from educational blogs such the CollaboratEd.org.uk Blog (@Collaborat_Ed), Neil Atkin’s Blog (@natkin), maybe this Blog you are reading and, one of my favourite, Gavin Smart’s Blog (@GavinSmart).

After a long period of hybernation the Croesy Physics online channel is about to become active again with a very exciting project that will see Croesyceiliog Yr13 Physics Students collaborating with learners at John Cabot Academy in Bristol to create and broadcast live online revision clubs!

Helen Rogerson (@hrogerson) is John Cabot’s Head of Physics and she will support her students once a forenight in creating and broadcasting their sessions from Bristol, and I (@asober) will do the same with my students from Cwmbran. We will take it in turn to broadcast on our Croesy Physics Livestream channel and we would love to see many of you watching live and engaging with our students. In fact, there will be a 10 minutes Q&A session at the end of each event for the people who are watching from other schools, or from home. People can ask questions using the Livestream chat on the online channel, or by using the twitter hash tag #croesybot.

Our live revision clubs will be broadcast live every Tuesday between 15.15 and 15.45 and our first event will be on the 15th November with the topic “The Motor Effect”

Each session will also be available on demand after the event and we hope that our service will become a really useful revision tool for our learners as well as for students in other schools across the world!

Please support our efforts by watching, chatting, sharing, tweeting, etc…

For help on setting up a similar activity see these resources I have uploaded on the TES website.

I am finally finding literally 5 minutes to catch up with a few things I have been doing since the beginning of the term and I wanted to share with you how I am using kidblog.org to create collaborative feedback between different schools and cross-phase. Our Yr12 Blog is here.

I believe allowing our learners to Blog is a powerful learning strategies for a number of reasons. Firstly, our students get a real audience and are more likely to take their assignments seriously and be enthused by the thought of communicating their work to the world. That is why it is so important for them to see comments appearing on their posts, as they get the feeling that their efforts are appreciated by others! Also, comments are a powerful and simple means to peer assess each other’s work, as well as, obviously, for the teacher to leave some feedback too.

So, I introduced my Yr12 to our CroesyPhysics Blog and set a couple of assignments for them. The first is something I have been doing for the last couple of years and it is about the learners writing poems to describe the Photoelectric Effect, more about it on this previous Blog post. But the second was a collaboration between our Yr12 learners and a Yr6 class  at Highlawn Primary School. In these Blog posts our learners had to explain energy levels and photon absorption and emission to an audience of 10 year old pupils. You can read the Blog post to set the assignment here. Our Yr12 students could present this Physics topic in whatever form they wanted, but it was very clear to the majority of the Bloggers that they needed to find a way to get their message across in a simple and coherent way, and that they could not assume anything, not even that the Yr6 learners would know what an electron, or an atom is!

So, I gave them a link to the PowerPoint I would have normally shown them on the topic and told them to use that and their text books to gather the information they needed to support their creations. I was pretty confident they would not copy and paste, because if they had, they would have failed to be understood by the Yr6 learners, who are reading our Blog posts and leaving comments to feedback on our students’ presentation, clarity and accuracy. It must be said that the comments we have had so far are really thorough and very well written for learners of that age! Learners at Highlawn Primary certainly know what it means to reflect on learning.

I think we’ve had some really good Blog post so far and this excercise has been useful for our learners, but I would love to hear your opinions and if you can spare a couple of minutes, please read through some of our learners’ work and leave a comment for them here! They will be thrilled to see others value their work.

I have the great pleasure of introducing my first Guest Blogger, Zvi Schreiber, who is a really interesting Author. He looks at the teaching and learning of Physics from a very different angle with his brand new book Fizz: Nothing as it seems.

Thanks Alessio for inviting me to Alessio’s Blog, to talk about why I chose to present the history and principles of physics in a non-traditional way: through a fictional novel, named “Fizz”.

Years ago I learned physics in the traditional way – text books, equations, lots of exercises. I loved it. But coming back to physics after years in the world of business, I found that my high school and college education had completely neglected other aspects of physics – and that those other aspects are fascinating to a wider audience who perhaps don’t like equations.

Firstly the physicists. Revisiting physics I learned more about Galileo’s mortal struggle with the Pope who had previously been a personal friend, and his battle against the entrenched two-thousand-year-old ideas of Aristotle. As the first physicist, Galileo showed incredible flare for presenting his ideas to a hostile public and willingness to risk his life.

I learned that Isaac Newton spent more time on alchemy than physics, and that his unpleasant personality may have been amplified by mercury poisoning. Michael Faraday, inventor of the electric motor and generator, was an apprentice bookbinder, the uneducated son of a blacksmith. William Herschel’s sister, overcame dwarfism and family prejudice to become an important astronomer in her own right.

These are just a few of the inspiring stories I had missed in school. The great physicists were real people and I wanted to present them as such.

Secondly many concepts in physics evoke an emotional as well as rational response. The vastness of the universe. The strange idea of action at a distance – introduced by Newton, eliminated by Einstein, reintroduced in quantum mechanics. The idea of an orderly deterministic universe attacked with the successive discoveries of entropy, chaos, and eventually random quantum fluctuations. Some hints at a possible multiverse. A novel allows me to explore Fizz’s response, as a young woman, to these weird revelations about the universe we call home.

There was an important precedent for an edu-novel – Sophie’s World – which helped me and millions of others to learn about philosophy in the 90s. I hope that now Fizz will take her turn alongside Sophie, and help a few people to learn more about our universe and about the bizarre series of people who explored it.

Zvi Schreiber is author of Fizz: Nothing is as it seems a new edu-novel about physics – see http://www.fizz-book.com

Back to me now, Alessio :-), because I would like to give you my impressions about the book. I read it during the summer holidays and it was a really enjoyable and easy read. The book reads very well and it always leaves you with the need to read and learn more at the end of every chapter. I am sure it is partly thanks to Physics, but the way Fizz explores and discovers the laws of Physics is truly fascinating and a great way to learn something about the History of Physics, as well as getting a coherent overview of the laws of Physics which are all connected to each other and not a “modular exam” 🙂

I also like the fact that there are virtually no formulae, not because I don’t like equations, but because it helps the learners to focus on the processes and it reinforces Physics concepts without distracting too much from the narration. Moreover, the situations Zvi built in the novel are memorable and give you that sense of awe and amazement the Scientists mentioned in the novel must have felt in those great moments of discovery!

Another really nice aspect of the book is that the main character is a school age girl who has a genuine passion for how the universe works and she is ready to risk everything to satisfy her thirst for knowledge. This will hopefully encourage and inspire girls to pursue a Physics career!

Nothing happens randomly in Zvi’s book and even the many truly unexpected twists that occur are used as analogies to explain Physics concepts and, believe me, one of these twists you will never guess until you get to those pages 😉

Our Yr12 and 13 will be part of a pilot project this year to test the effectiveness of Fizz’s great adventure in motivating students to learn about Physics and in raising standards. So, watch this space as I will post our learners progress and their impressions on the book.

Science Rap! Start to clap…

Posted: January 18, 2011 in Institute of Physics, Thoughts and ideas
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This sound like a really interesting competition. Get your kids to Rap about Science! Writing poem, rhymes and songs is a really engaging way for students to remember and understand Science concepts more deeply. In fact, writing a song which has certain parameters and with rhymes is a fantastic tool that helps learners to develop not only Literacy skills, but also thinking. A Rapper often uses his/her wit and humour to get their message across with the interesting way they have to play on words. Transferring this skill to Science is really useful, because it can help learners to represent difficult scientific concepts in a more memorable way and think deeply about the meaning of physical, chemical and biological processes as well as building their own models to consolidate understanding.

A good example is the first verse of this poem written by one of my yr 12 pupils last year:

The photoelectric effect is easy

UV light hits the metal causing it to become a little queasy

The metal releases a photoelectron without a fight

More electrons are released when the intensity is increased of the light

I am sooooo pleased to announce that the fantastic online TV show our Yr10 pupils produced last year, the one and only “EM Spectrum Show“, was awarded first prize at the Guardian Classroom Innovation Awards at BETT 2011!

My Yr10 students put together a really creative programme of resources that we used to broadcast live as our “EM Spectrum Show!” on the 17th December 2009. The original plan was to broadcast from the school, but unfortunately our school network filtered the stream from our classroom, so my students and I decided to record their work and broadcast the show live from my house. In many ways this turned out to be a very valuable alternative, because it meant the world to our children to be able to watch the show from their houses and know that leading Educators like, Les Foltos (Director of edLAB Puget Sound Center for Teaching), from across the globe were watching and praising the educational value of their work. Also, the students’ parents could watch the show with their children and become involved and engaged with their learning on a completely new level.
What I like most about this project is that our children chose to use free software for the majority of their work, but still produced a really engaging, creative, rich and fun programme that contained a wealth of really good Science in it! We used mainly free Microsoft software like Photo Story 3, Songsmith, Movie Maker and Community Clips, and we created our very own online TV Channel with Livestream (http://www.livestream.com/croesyphysics). Some people get the impression that to create really innovative and engaging activities for our children they need state of the art equipment and spend large sums of money, but I believe this project proves just the opposite. In fact, all our students had was a laptop between two, or three, and a headset with microphone and still got involved in true active learning!
Winning the Guardian Classroom Innovation Awards is simply amazing, because we know we were against other fantastic projects.
We would like to thank all the people who supported and believed in our project and especially ASUS for their overwhelming generosity, which will allow us to continue to engage even more regularly in projects like this one! In fact, we will now have the really difficult task to choose from their amazing range of great hardware and spend the £7500 award they so kindly offered to support these awards. By sponsoring an initiative like the Guardian Classroom Innovation Awards ASUS has shown that they put innovation and education at the heart of what they do and I am proud to be sponsored by such a company!

I found the iSeismo App for iPhone a few months ago thanks to an email on the PTNC (the Institute of Physics mailing list). It is a free App and also a brilliant one. I am developing resources for the WJEC Separate Science Specification (Physics 3) here at NGfL Cymru (National Grid for Learning Wales) and one of the topics is Seismic Waves, so I couldn’t resist the temptation to create an activity that would take advantage of such a great App!

iSeismo displays a seismograph for movements along the x, y and z axes using the inbuilt accelerometer in the iPhone and it is very realistic and quite accurate too. The needles look just like a real Seismographer writing on paper rolls, but with this electronic seismographer you can freeze the screen and pause it at a particular moment, as well as other interesting things.

I am giving you another sneak peek of what’s coming soon on the NGfL Cymru website. Below is the video that I created this morning to go with this activity in Wallwisher. The cool thing is that when the iPhone was at rest I received an email and the phone vibrated. The needles on iSeismo showed a vibration along the x and z axis, but not on the y-axis. So, the vibrator must be fixed onto a plane which is perpendicular to the y-axis. I bet you didn’t know that about the iPhone, did you? At least about the iPhone 3GS.

I created the Wallwisher wall as an example for teachers, but to use it with your classes you would need to register with Wallwisher and create your own wall by linking the video to the YouTube video in this blog.