Posts Tagged ‘experiments’

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!)

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.

Dr Frederick Banting - pioneer of insulin treatment

This week marks the 90th anniversary of the discovery and isolation of insulin by Dr Frederick Banting, a discovery that has saved and improved the lives of millions of diabetics.

What is Diabetes?

Diabetes is a serious disease that affects over 250 million people globally, in which the body either doesn’t produce enough insulin (Type 1) or doesn’t respond to the insulin that is produced (Type 2). This leads to a high blood sugar level, and this causes a variety of medical problems if not managed. 90% of cases are Type 2 diabetes.

 
What is insulin?

Insulin is a hormone produced by the pancreas. It plays a central role in controlling and regulating the amount of glucose in the blood. It does this by causing cells in the liver (and some other cell types) to store the glucose as glycogen. Insulin is injected by Type 1 diabetics as part of their treatment. Type 2 diabetics may sometimes need to inject insulin, but their treatment and management focuses mainly on lifestyle and diet control.

How was insulin discovered?

Before insulin was discovered, diabetes caused death in nearly all cases. The only treatment available was a strict controlled diet and this only gave the patient a few more years. In the 19th century a German medical student called Paul Langerhans had identified a set of cells in the pancreas that didn’t seem to have a function. (These were later identified as beta-cells which produce insulin). A few years later two other German scientists showed that the pancreas was involved in controlling blood-sugar, because they found that dogs that had their pancreas removed developed diabetes.

Location of the pancreas

In 1920 Dr. Frederick Banting, a Canadian surgeon in Toronto, developed a process for isolating a secretion from the pancreas that was shown to prevent diabetes when injected into dogs that had had their pancreas removed. With this isolated secretion now named ‘insulin’, Dr Banting and his team started testing on human subjects, beginning with themselves. They managed to develop the correct dosage and in January 1922 gave insulin to a 14 year old diabetic boy, Leonard Thompson. The insulin worked perfectly, and Leonard recoverd from near-death. In 1923 Banting was awarded a joint Nobel Prize for Physiology or Medicine and a medical company went on to mass produce insulin.

Leonard Thompson - the first person to receive insulin.

Whilst insulin doesn’t cure diabetes, it means diabetics are able to regulate their blood glucose levels and stay alive. Perhaps you’ll agree that the discovery of this treatment is one of the great medical advances of the 20th century.

Dancing Fire!

Posted: January 7, 2012 by Mr Pimentao in Physics, Uncategorized
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Sound seems to have caught the eye here at Loreto’s science cyberspace presence.

Whilst “youtubing” aimlessly like a headless chicken, I came across several videos showing a Ruben tube.

This is a perforated tube connected to a supply of flammable gas on one end, and attached to a speaker on the other end. As the gas flows through the tube holes, the (standing) sound wave created inside the tube by the speaker causes areas of high and low gas pressure. If you fire the gas up, it becomes an impressive flame show. The height of the flame is taller in the areas of higher pressure, so it acts as a visual display of the sound wave that travels inside the tube.

Some people like to play a single note on the speaker and are happy with that. Others experiment with all kinds of sound : from dubstep to glam rock!

Videos:

Mythbusters playing with Rubens tube

Another one bites the dust on Rubens tube

Bad romance on Rubens tube

Non Newtonian fluids

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