Light bulbs as we know them are set to change. A group of European countries, including Britain, has decided everyone should be made to use energy efficient bulbs instead. Low-energy bulbs use less power than traditional ones and last up to 12 times longer. The plan is to help cut the emission of dangerous gasses which some people blame for causing climate change. Low-energy bulbs are a bit more expensive than traditional ones, but in the long-run they can save money because they're using less power. Australia says it will get rid of traditional light bulbs by 2010.

Did you know?

1. Lightbulbs were invented by Thomas Edison in 1879.
2. Energy efficient bulbs last up to 12 times longer than old fashioned ones.
3. In most homes, lighting accounts for 10 to 15 per cent of the electricity bill

This story was taken from  BBC newsround

Have a look at these sites:

How light bulbs work? home.howstuffworks.com/light-bulb.htm

How does a halogen light bulb work? home.howstuffworks.com/question151.htm

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Tastebud Tickler

Find out how sensitive your tastebuds really are!

You will need:

• Fruit pastilles, jelly beans or similar fruit-flavoured sweets (vegans can use pieces of fruit or cooked root vegetables)
• A blindfold
• A glass of water
• A friend who's happy to be a food tester for you

What to do:

1. Put a blindfold on the food tester.
2. Take a few sweets of different flavours and give them to the tester, so they have an idea what the flavours are like before they have to do the real work.
3. Let them have a sip of water in between different flavours.
4. Now give them a mystery sweet and ask them to guess the flavour.
5. You can try this a few times to see how good they are at identifying flavours - but they might get a bit sick of chewing the sweets!
6. Here comes the real test - get them to hold their nose while they are tasting the next sweet. They have to tell you the flavour before they let go of their nose. Not easy, is it?

What’s going on?

Our senses of taste and smell are strongly linked. It has been suggested that the taste sensors on our tongue can only detect four different tastes (sweet, salty, sour and bitter). So most of what we know as 'flavour' is a combination of taste with smell. Think how food tastes very bland when you have a cold (and a blocked nose) – it's because the 'part smell' of the flavour is missing!

More ideas

Get your friend to keep holding their nose. Then substitute in a bit of rock salt, a wedge of lemon or some of those disgustingly flavoured vegetable jelly beans and see if your friend notices.

this experiment came from...

'Sensation', a science centre based around the senses in Dundee.

And features in Planet Science’s The Little Book of Experiments

http://www.planet-science.com/experiment

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