Posts Tagged ‘physics’

On 4th July students and staff took part in the 24 Hour Water Rocket Challenge, a World Record attempt. Organised by the University of Central Lancashire and NASA, the aim is to have as many water rockets launched around the world in a 24 hour period.

Water rockets are really simple to make – they’re just 2L bottles with some water and high pressure air, but the result is amazing. Taking off at speeds of around 90mph, experiencing forces 60 time greater than gravity and reaching heights of at least 45m, they’re a great way to experience forces and momentum in action.

We were lucky enough to have two witnesses from local business Cotswold Camping (thanks Jim and Ant) and managed to achieve 16 separate launches over lunchtime. I’ll update this post when I hear if the World Record was beaten, but it’ll take a while for the organisers to count and verify all the results.

Thanks to all those that took part or came and watched.

Read more at the St Albans Review newsite

A water rocket blasts off from Space Station Loreto! (photo from St Albans Review – thanks!)

Advertisements

The 21st of July 2012 played host to the annual Maths and Science Day. Maths and Science Day allows all year 8 students to work off timetable for the enire day, working in teams to solve scientific and engineering challenges. Deviating from the task of previous years (parachutes for eggs) the teams this year were set the challenge of building a bridge that covers a 50cm span using only spaghetti and hot-melt glue.

The girls got straight to work, ably assisted by Yr 12 students. They worked really well together, with each student contributing to the team design.

Eventually, when all the bridges were built it was time to test them. Bridges were gradually loaded with more and more force until they broke. The winning team would be the one with the highest load:weight ratio. After a nailbiting testing session, a winner was declared – Team 25 with a load:weight ratio of 11:1!

Bridge 25 – the winning bridge!

After this the teams got together to create a poster explaining their design, the science behind the engineering of bridges and an evaluation of their bridges performance. Team 10 were judged to have the best poster for their careful analysis of why their bridge collapsed with only 10g on it!

A spaghetti bridge, inspired by a Warren Truss bridge

Every team worked incredibly well – their bridges may not have held a great load but they all produced a structure which they could be proud of.

Testing bridges

Funding for the purchase of the hot-melt glue guns and the spaghetti was kindly provided by the Institute of Physics (IoP) http://www.iop.org/ , so many thanks to them for making this event possible.

On 7th February 48 students from Year 11, (accompanied by Mr Bilton, Miss Vine, Mr Pimentao and Miss Gilleece) travelled to Essex to visit the npower-operated Tilbury Power Station. The students study the generation of electricity as part of their course, so this was an excellent opportunity to see where it all happens. The Tilbury site was originally a coal-fired power station, but this year it switched to using biomass as the fuel source, as part of a programme to be ‘greener’ and depend on renewable sources.

Tilbury Power Station

The biomass used at Tilbury is wood pellets, produced from the sawdust and waste of the Canadian lumber industry, so it’s a good use of a material that would otherwise just be wasted. It also has less impact in terms of CO2 production than coal, because it’s not burning carbon that’s been locked away for millions of years.

Properly kitted out in hard-hats, ear defenders and high-visibility jackets the students were taken on a tour of the power station, at one point standing inside a 65m furnace which reaches temperatures of 1500ºC (luckily for the students it wasn’t on at the time…). The scale of the facility is hard to imagine, but it gives you an appreciation of engineering behind the process.

Safety first - hard-hats and ear defenders!

The process of electrical generation is actually remarkable simple. When the biomass arrives it is crushed and then blasted into the furnace where it burns. The furnace is lined with pipes that contain ultra-pure water. As this water heats up it turns to steam. This high-pressure steam is used to turn turbines (converting heat energy into kinetic energy), and the turbines rotate an electro-magnet within a coil of wire. The movement of a magnet within a coil of wire creates the electrical current (thanks Faraday!) and that’s all there is to it.

Generating electricity - what's happening inside?

The students were also able to study some of the chemistry and biology surrounding the issue of power generation. Using conductivity meters the students recorded how many dissolved ions and minerals were in drinking and filtered water. They then compared it to water that had been through an ion-exchamge resin and were surprised to see that there were no ions left at all. This super-pure water (which actually tasted a little bland) has to be used in the power station to prevent damage to the pipes (picture the inside of your kettle..). The students then had a look at the local water quality by pond-dipping and looking for indicator species; species that tell you how clean the water is by their presence or absence. Having found a variety of insects including Common Backswimmers, Damselfy nymphs and Diving Beetles (and even some fish) everyone was surprised to conclude the water so near a power station was actually good quality and supported a diverse community.

Damselfly nymph - this larval form indicates good water quality

Common Backswimmer - this insect swims upside down

The students had a really good time and certainly learned lots about where their electricity comes from and how best to manage our energy resources so that we can live in a sustainable and ecologically-sensitive way. Many thanks too to the staff at the power station for giving us such an enjoyable day!

Non Newtonian fluids

Posted: January 4, 2012 by Mr Pimentao in Physics
Tags: , , , ,

Many people have heard of Sir Isaac Newton. He is famous for developing many scientific theories in mathematics and physics. Newton described how ‘normal’ liquids or fluids behave, and he observed that they have a constant viscosity (flow). This means that their flow behaviour or viscosity only changes with changes in temperature or pressure. For example, water freezes and turns into a solid at 0˚C and turns into a gas at 100˚C. Within this temperature range, water behaves like a ‘normal’ liquid with constant viscosity.

Typically, liquids take on the shape of the container they are poured into. We call these ‘normal liquids’ Newtonian fluids. But some fluids don’t follow this rule. We call these ‘strange liquids’ non-Newtonian fluids.

The viscosity ( how “runny” a fluid is) of a non-Newtonian fluid depends on things such as the stress, or pressure applied to them. This means that a quick change in the pressure applied to such a fluid might change its viscosity.

Cornflour solution on a speaker cone.

This is the reason that explains the formation of these cornflour “creatures” . Corn starch is a shear thickening non-Newtonian fluid meaning that it becomes more viscous when it is disturbed. The changes in pressure created by the sound vibrations change the viscosity of the fluid, and the result is fantastic. Check it out here.

Another classic example is Mr. Tickle walking on custard.

A Celebration of the Moon

Posted: January 4, 2012 by Mr Bilton in Gallery, Physics, Space
Tags: , , , , ,

The US Space Agency NASA has succeeded in placing a set of twin satellites in orbit around the moon. The satellites, called the Grail Twins, are set to map gravity variations across the surface of our nearest neighbour.

This will allow scientists to understand the formation of the moon in more detail, and even to test recent suggestions that Earth may once have had two moons.

So, to celebrate this here are some pictures showing different aspects of a very familiar face.

This slideshow requires JavaScript.

 

What’s the link between zebras, climate change and giant lasers?

The answer is they’re just a few of the topics discussed by some of the country’s top scientists at the GCSE Science Live! Event on the 25th November. Mr Bilton and Mrs Camm took 32 members of 11 Sci 1 to the talks held at the Dominion Theatre, London.

The event attracted around 1600 GCSE students from across the country, who had gathered to listen to five scientists discuss a range of fascinating topics.

Prof. Steve Jones, a geneticist, talked about the relative merits of the nature vs nurture argument. Prof. Sir David King, who was once the Chief Scientific Adviser to the Government, spoke about Climate Change and the problems that will need to be tackled in the future. The infamous Prof. Richard Dawkins posed the question ‘Is Evolution Predictable’ and Dr Kate Lancaster explored the use of high-powered lasers to trigger nuclear fusion reactions – a source of incredible energy. The talk was concluded by chemist Prof. Andrea Sella, who looked at the connection between chemical reactions and the patterns found in the skins and fur of animals.

The talks were delivered in a thoroughly engaging manner by scientists that conveyed their passion and love of the subject. The students really enjoyed themselves and were still discussing the lectures several days later.

The 5 scientists who spoke at GCSE Science Live!