Science by Email 25 November 2011

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	25 November 2011
The new material is light enough to rest on the head of a dandelion. News: Not so heavy metal By Patrick Mahony Researchers at HRL Laboratories in the USA have created what they call ‘the world’s lightest material’ – and it’s made of something that should normally sink like a ball of lead. The material is mainly composed of nickel, with small amounts of phosphorus included. Nickel is usually denser than steel, but this material is 100 times lighter than Styrofoam and is light enough to rest on the head of a dandelion. How do you turn something so heavy into such a light material? The key to answering this question is to look at the structure of the material. Think of a building such as the Sydney Harbour Bridge. It occupies a large volume and is also strong. However, the amount of steel used to make it is small compared to the space taken up by the tower – most of the space occupied by the bridge is filled with air. The researchers took a similar approach, just on a much smaller scale. The new material is 99.99 per cent ‘open volume’ – in other words, it’s mostly empty. The remaining 0.1 per cent consists of hollow tubes of nickel and phosphorus that are 1000 times thinner than a human hair. The tubes are arranged in a lattice to make it strong while keeping it lightweight. It is not only light, but has other useful properties too. It can absorb large amounts of energy, and is able to recover its shape after being compressed. Its inventors think it might have future uses in batteries, shock absorbers and assisting chemical reactions. The development of materials such as this highlight that heavy metal may well be making way for something lighter. More information HRL researchers develop world's lightest material CSIRO link: Light Metals Flagship Careers Careers in metallurgy
You will need these materials.   Pour water into the pan.   Remove your shoes and socks and step into the pan of water.   Remove your foot from the water and immediately step onto the paper bag.   Use this diagram to determine what type of arch you have: 1 = high arch 2 = normal arch 3 = low arch/flat foot Try this: Walk this way   You will need A shallow pan Water A brown paper bag What to do Place the pan on the ground and place the paper bag in front of it. Pour water into the pan. Take off your shoes and socks. Put one foot into the pan so that the sole of your foot is wet. Step out of the pan onto the paper bag. Step off the bag. Look at your foot print and use the diagram to determine what type of foot you have. What's happening? The bottom of your foot has a heel at the back, a fleshy ‘ball’ behind the toes and a curved arch in between. The arches are important for supporting weight and also for walking, running and jumping. Different people have different types of arches. If your footprint shows the heel, ball and about half of the arch of your foot, you have normal foot arches. If you can see most of the arch of your foot in your footprint then you have flat feet. If you could only see the heel and ball of your foot, and little or no arch in between, then you have high arches. Normally when you walk your heel hits the ground first. As the weight moves forward onto the ball of the foot, the ankle rolls in slightly. This rolling movement is called pronation. Pronation is important for distributing the impact of walking evenly through each foot. Some people will roll their ankle inwards more than others. This is called overpronation. Others will hardly roll their ankle at all, which is called underpronation. Applications People who overpronate usually (but not always) have flat feet, while those who underpronate tend to have high arches. Underpronation and overpronation have the potential to cause injuries to the foot, ankle and lower leg. A number of sport shoes and insoles are designed specifically to reduce the effects of under and overpronation. An easy way to see if you underpronate or overpronate is to look at an old pair of shoes. If the inside edge of the shoe's heel is more worn than the rest of the heel, then you overpronate. If the outside edge of the heel is more worn then you underpronate. If you can’t see a difference in the wear on your shoes, then you walk with normal pronation. Try a Science by Email activity about a different kind of arch More information Pronation, explained By Patrick Mahony View online version Quiz questions 1. Most planets in our Solar System rotate anticlockwise except for two. Which two? 2. Where would you find a capacitor? 3. Which chemical element has the symbol ‘Au’? 4. What are the only mammals that can fly? 5. What is the main cause of coral bleaching? Did you know? The regent honeyeater is a threatened species native to south-eastern Australia. Recently, a captive-bred female was found to have successfully reproduced in the wild, boosting efforts to save the species. Website See it! See the Milky Way like you’ve never seen it before in this video. Do it! Create your own earthquake with this simulator! Events ACT: Mt Stromlo Observatory Open Day The Australian National University Research School of Astronomy and Astrophysics is celebrating 100 years of observing. As part of the celebrations they are holding an open day at the Mt Stromlo Observatory. Activities include talks, tours, solar observing, live music, a jumping castle and human sun dial. The open day is on Sunday 4 December from 10.00 am to 4.00 pm. Entry is free! For more information, call the Mt Stromlo Observatory on (02) 6125 0230. Science at night, Saturday 26 November at 9.00 am on Network Ten This week, SCOPE is up WAY past its bed time searching for signs of science during the night! From things that glow in the dark, to nocturnal animals and night vision technology, this episode is as full as the moon! So sleep on it, but don’t forget to wake up and join Dr Rob as he once again proves that the ordinary becomes extraordinary, under the SCOPE. Next episodes: Thursday 1 December: Team sports Saturday 3 December: Oxygen Want to have your own episodes of SCOPE to watch whenever you feel like it? Click here to download them directly into your iTunes folder, or go here to download iTunes. Charges apply. Quiz answers 1. Venus and Uranus are the two planets in our Solar System that don’t rotate counter clockwise. 2. Capacitors are typically found in electric circuits. 3. Gold has the symbol Au. 4. Bats are the only mammals that can fly. 5. Rising water temperatures is the main cause of coral bleaching. Researchers from the ARC Centre of Excellence for Coral Reef Studies have shed new light on the processes involved in coral bleaching and death. Science by Email is a CSIRO publication. The Department of Agriculture, Fisheries and Forestry and bankmecu are proud partners of Science By Email. Editor: Mike McRae | Manage your subscription | FAQ

 

 

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