4. Events for Teachers
1. Prac Investigations at home
Last week's online discussion had over 40 participants. There was an exciting range of ideas shared. Many aspects were covered including: Possible topics, phone apps, sources of secondary data, timelines, authentication, etc
The notes from the discussion are now on our website here .
Investigations at home: Our homes have many items that can be used in an investigation, such as balls, toys, rubber bands, plastic bottles, cloths, etc. Measuring instruments can include kitchen scales, ruler, stop watch apps, indeed there are a range of measuring tools in apps such as Phyphox, The Physics Toolbox and SparkVue. The video analysis software, Tracker, is also a very powerful tool.
Investigations on Video: Videos of investigations that students can pause to extract data or use Tracker, give students access to real data with associated uncertainties. Vicphysics is currently preparing videos for several topics including:
Other teachers are preparing videos on the Saxon bowl as well as other ball experiments.
- How the strength of the magnetic field between two bar magnets varies with separation as measured with a top loading balance.
- How the strength of the magnetic field between two disc magnets varies with separation as measured with a top loading balance.
- How the magnitude of the electrostatic attraction between a charged rod and a metal sheet varies with separation as measured with a top loading balance
- How the loss of charge from a charged rod varies with distance from low speed fan as measured by a top loading balance.
- How the energy loss and the force of impact of the bounce of a basketball varies with drop height
- How the energy loss, force of impact and compression of a spring vary when a set of metal washers fall down a rod onto the spring from various heights
- How the energy loss, force of impact and compression of a spring vary when a sets of metal washers of different mass, fall down a rod onto thr spring from a fixed drop height.
These videos will be available from 17th August in a folder on the Vicphysics Google Drive rather than on our website. Teachers may request access to the drive and download the files for their students. More details next week.
Lab techs: In some schools, the lab tech may be still coming in, as it is their workplace. They may be willing to set up and video some experiments and investigations for you.
Online Experiments: There are not many experiments that can be controlled remotely, but the Australian Synchrotron has two. Freely Available Remote Labs (FARLabs) enable students to control an experiment and take their own measurements. There are two: Photoelectric Effect and Diffraction of Light. They are designed as formal experiments, but may allow greater investigation, for example how does the distribution of energy of photoelectrons vary with the frequency of the light.
Secondary data: The study design for 2020 also offers the alternative of using data from other investigations. An obvious source is the investigations by previous students. School should have log books from previous years. This could be a rich lode, but it may take some time to extract the right ore and then refine it to the point where it becomes useful. It is also a resource that could be shared with other schools. If you have any to share Vicphysics is happy to make it available in a controlled way.
Simulations: There are several websites, such as PhET, Walter Fendt, etc that provide simulations as educational material. They may have some value as topics for investigations, but they are usually limited as far as repeated trials and uncertainty in the data recorded. These can be found here on our Apps and Applets webpage.
The Vicphysics Teachers' Network set up a Job Ads page on our website to assist schools in finding a physics teacher, either to be a LSL replacement or to fill an ongoing position or just to cover an extended sick leave.
This webpage is updated every weekend. The webpage also has a link on how schools can register a position and also lodge a payment for this service.
- There are two Government schools seeking a physics teacher: The Lakes South Morang College (2 positions) and Wantirna College.
3. Events for Students and General Public
a) Behind the Scenes of Big Science, 7:00pm - 8:30pm, Weds 19th August
This National Science Week ANSTO are giving the public a unique opportunity to see behind the scenes at the Australian Centre for Neutron Science, online and for free. Students can see the different kinds of instruments the Centre hosts, and hear the results that they bring. Five of their scientists will each walk the students through their world-class science machines, and after there will be a live Q&A where they can quiz them more. This is a rare opportunity to see behind the scenes of this big science factory.
When: Wednesday 19 August, 7pm-8.30pm (AEST)
To register, click here. There is no cost.
b) UNSW Bragg Prize for Science Writing for Years 7 - 10. Entries close 27th August.
The 2020 Theme is 'The Big Ideas saving the Planet'.
Students write up to 800 words to describe some scientific research that has delivered a solution that the student believes could change the future for the planet.
This website has entry details, as well as FAQs, Teacher's resources and Writing tips.
a) 2020 Physics in the Cloud: A Physics Free-For-All Variety Night, 6:00pm, Friday, 21st August
Physics in the Pub has gone virtual! An AIP Initiative.
Tiny magnets, cell goop and the future of the Universe
"We’ve digitized and uploaded our scientists and they’ll be streaming to you from the cloud, about the complex protein structures in our cells, how tiny magnets can cure cancer and, well, the philosophy of everything!
There’ll be songs, poems and quizzes, so have your device ready. Grab yourself a drink and join us online, with host Dr Phil Dooley of Phil Up On Science."
Cost: Free, thanks to the AIP
For more information, click on Facebook here
To register, click here.
5. Physics from the Web
Items selected from the bulletin of the Institute of Physics (UK).
Each item below includes the introductory paragraphs and a web link to the rest of the article.
New insights into why a hard steel razor blade is dulled by cutting soft hairs have been gained by a trio of researchers at the Massachusetts Institute of Technology. Aa series of experiments recreated the shaving process and found that dulling is a result of microscopic variations in the structure of a blade and the angle at which a cut is made. The team suggests that nanoscale improvements to blades could boost the performance of cutting tools.
Most modern cutting edges are made of hardened steel, which is much harder than commonly cut materials such as hair and food. Indeed, the steel used to make razors is more than 50-times harder than human hair. As a result, scientists have long been puzzled exactly why such blades dull so rapidly after cutting seemingly soft materials.
It had long been assumed that sharp edges are dulled by basic wear mechanisms such as the cracking of brittle steel surfaces and the rounding of edges. However, little had been known about how these processes relate to the complex ways that blades and materials interact during the cutting process on a microscopic scale.
b) Portable sensor detects biomagnetic signals in noisy outdoor environments
A portable sensor that can detect tiny biomagnetic signals from the brain and heart – without the expensive magnetic shielding needed by current magnetoencephalographic techniques – has been developed by researchers in the US. The low-cost set-up, which is small enough to fit in a backpack, can operate successfully even near to power lines and a railway, and could find application in field triage, brain–machine interfaces and even precise magnetic navigation.
Magnetometry in the form of magneto- and electroencephalography (MEG and EEG) can provide vital insight into human brain and cardiac function, with resolutions that exceed alternative techniques like functional MRI and positron-emission tomography (PET). Commercial MEG systems, however, are expensive to operate and come with a sizeable footprint – requiring both large-scale magnetic shielding and cryogenic cooling systems – which also limits the activities that they can be used to study.
c) ‘Cartwheeling’ light reveals new type of polarized light-matter interaction
Technologies that rely on interactions between matter and polarized light usually stick to the well-understood effects of linear or circular polarization. Researchers at Rice University in the US have now opened the door to fresh approaches by studying how matter reacts to an additional form of polarization. This form, known as “trochoidal” polarization, is characterized by a “cartwheeling” motion in light’s electric field that can occur in either a clockwise or anticlockwise direction. Since matter can distinguish between these two directions, trochoidal dichroism could be used to develop novel spectroscopic tools.
Circularly-polarized light, in which the direction of the electromagnetic field rotates in a helical or “corkscrew-like” fashion as it propagates through space, is commonly used to study the conformation of small biomolecules such as proteins, DNA and amino acids. These studies are possible because such molecules are chiral – that is, their structures have a “handedness” that makes them absorb left- and right-circularly-polarized light differently, a phenomenon known as dichroism. Linear polarization is also widely used, for example to control reflections and glare in sunglasses.
The light polarization the Rice researchers studied is very different from these more familiar types. Rather than following a helical progression, the direction of the electromagnetic field in trochoidal light turns end-over-end as it propagates, rotating either clockwise or anticlockwise as it goes. “Rather like a rolling hula hoop,” explains study lead author, Lauren McCarthy