Balancing Brooms - finding the centre of mass Listen Now Download as mp3 from the show Should I Lie Down to Tan? What you Need What to do Point the index fingers of both hands and hold your hands apart but parrallel. Get someone to balance the broom horizontally on your two index fingers, making sure you keep them level. Now gently move your fingers together. What may happen You should find that as long as you keep your fingers level the broom stays balanced, even as they get very close together. Why does it happen? When you start off holding the broom inevitably one finger will be closer to the centre of mass than the other. This means that more of the weight will be sitting on the closer finger, so it must be pushing upwards harder. The larger the force between the finger and the broom the larger the maximum frictional force it can provide before it slides. The finger furthest from the centre of mass will therefore be able to slide the most easily, and it moves until it is no longer the furthest from the centre of mass. Dave Ansell Multimedia
Measure Up with a Homemade Thermometer Key concepts Temperature Measurement Thermal expansion Introduction Are you sometimes eager to understand how things work? Or excited about making useful objects and instruments yourself? Did you ever imagine you could build your own liquid thermometer? You'll be able to use it to track how temperatures vary with location—indoors or outdoors. Background Liquid-filled thermometers have been used for centuries to measure temperature. Scientists refer to the tendency of matter to change volume as a result of a temperature change as "thermal expansion and contraction." Materials Preparation Empty and wash the small, plastic bottle.The clear drinking straw will become the narrow tube of your thermometer. Procedure Add rubbing alcohol to the bottle, filling it about halfway up. Observations and results Did you see the fluid rise as you heated the reservoir and fall as you cooled it? Various liquids can fill the reservoir of a thermometer. Celebrating 175 Years of Discovery
Keep it Cool | TryEngineering Lesson Focus Lesson focuses on the engineering behind keeping food and other items cool. Students work in teams to develop a system to make an insulated liquid container that will keep chilled water as cool as possible for an hour using everyday items. Students will need to devise a way to have a thermometer rest in the water and be able to read the temperature throughout the hour. Age Levels: Objectives Learn about insulation, heat transfer, and vacuums.Learn about engineering design and redesign.Learn how engineering can help solve society's challenges.Learn about teamwork and problem solving. Anticipated Learner Outcomes As a result of this activity, students should develop an understanding of: insulationvacuumheat transferengineering designteamwork Lesson Activities Students explore how engineers have developed systems to keep liquids cool and learn about heat transfer, insulation, and vacuums. Resources/Materials Alignment to Curriculum Frameworks
Investigating heat transfer by conduction / Nature of Science Teaching Activities / Nature of science / Home - Science Online Levels: 3-4 NoS achievement aims: Investigating in science Contextual strands: Material world , Physical world Topic: Heat transfer Rationale Heat energy moves from regions of high to low temperature and can be transferred by conduction from one object to another if they are touching. While investigating heat transfer by conduction, students will make decisions about appropriate approaches and methods for gathering specific information. What you need A range of materials that represent heat conductors and heat insulators, for example, metals, glass, ceramics, wood, cardboard, and plastics. Note: Supporting activity resources are suggested below. Focus Can you think of situations when you might want to stop heat from escaping from somewhere? Exploration In groups, give students access to a range of the conducting and insulating materials. Reflection Did all groups have the same order of conductors using the first method? Activity resources Ministry of Education. (2003). Return to top
Inspire Her Mind Science There’s a young 4-year old girl shuffling through a chest full of various dress-up clothes. The copy asks: Does dress-up determine her future? Scroll to the left, and the girl picks up a princess dress from the chest. She walks over to a mirror and holds the dress in front of her. The girl in the mirror, representative of her imagination, is wearing the dress and holding a wand. Scroll to the right, and the girl picks an astronaut suit out of the chest. Technology There’s a father and daughter working on an electronic helicopter. Scroll to the left, and the father takes a soldering iron and starts working on the helicopter while the daughter watches. Scroll to the right, and the daughter reaches forward to connect a wire on the helicopter, making it work, as the rotor blades twirl. Engineering An 8-year-old girl sits on a deck and looks at some playhouse toys, such as a pink couch, and a pile of wood. Math A girl sits in a classroom looking ahead at the teacher.
Teaching with TLC: 10 ways to make physical science FUN! This month we've been completing lots of physical science lessons that my kids do not want to put down. I just love it when they are hooked on learning! My kids have been learning all about simple machines, matter, and electricity from the best science teachers at the Edison Home. What better place to learn about science than Edison's home! As you may already know, I REALLY like hands-on learning because those are the lessons that make learning stick. We watched Bill Nye, The Science Guy teach about Atoms in this great video! The kids used cereal to model the different spacing of atoms in matter. We made a 3-D atom using an orange, candy, and toothpicks. Here my boys are watching the video that is mentioned above. The teacher in the video had them make negatively charged and positively charged atoms. I was on a quest to make an edible atom. When we were creating the atom, one of my sons exclaimed, "Oh, now I get it! I can't believe how much learning took place during this lesson.
Physicists Achieve Quantum Teleportation of Photon Over 25 Kilometers For the first time, a team of physicists have successfully teleported a quantum state of a photon to a crystal over 25 kilometers away through a fiber optic cable. This effectively showed that the photon’s quantum state, not its composition, is important to the teleportation process. The team was led by Nicolas Gisin of the University of Geneva and the results were published in the journal Nature Photonics. With this new paper, Gisin’s team has successfully squashed the previous record they set a decade ago by teleporting a quantum state of a proton 6 kilometers. The quantum state of the photon is able to preserve information under extreme conditions, including the difference between traveling as light or becoming stored in the crystal like matter. To test this and ensure what they were observing was actually happening, one photon was stored in a crystal while the other was sent along optical fiber, over a distance of 25 kilometers.
Physics – News, Research and Analysis – The Conversation – page 1 The energy needed to pull magnets apart comes from you, and you get it from the food you eat. And the plants or animals you eat get their energy from other plants and animals, or from the Sun. All energy comes from somewhere. The award of a Nobel Prize in physics to Donna Strickland is an opportunity to build support for women in science, says one female physics professor. Donna Strickland is the first woman in 55 years to be awarded the Nobel Prize in Physics. Using lasers to trap and move particles changed the way we're able to study microscopic life. The way science is currently taught in southern African countries ignores the fact that the whole environment is a laboratory for learning. The new physics syllabus for year 11 and 12 students in NSW contains no mention of specific women who have contributed to the field, nor their work. Astronomers are voting to rename one of the laws of physics. Machine learning is changing the world in ways that we are just beginning to appreciate.
Te Reo Physics Resources Kia ora tatou Take a look at these experiments and follow the instructions and learn what Physics is about Atoms, Nuclei and Photons Circuits and Electromagnetism Eddy Current – Tank | Te Taika Konukura A strong magnet rolls down a copper plate, turning toward the centre of the copper plate as eddy current drag slows the inner face of the magnet more than the outer face. Electricity Generation | Te Mahi Hiko An aluminium vane swings slowly between the poles of a magnet while a plastic vane is unimpeded. Transformers A primer on transformers and their use in the electricity distribution grid. Trick Magnet | Auto Nuka One of two apparently identical steel rods passes easily between the poles of a magnet while the other unavoidably sticks to the magnet. Fluids and Thermal Gasses Floating Ball | Pōro Rewa A ball is suspended in an upward column of air and prevented from moving sideways by the reduced pressure near the centre of the flow. Light and Waves Computer Colours | Ngā Tae Rorohiko Mechanics