How to Float a Paperclip in Water
This is a great experiment to impress your friends and learn a little bit about surface tension too! All you need is a glass and a paperclip, so let’s get started!
What do you need?
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A glass of water
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A paperclip
Step 1
Just prove to yourself what you already know, if you drop a paperclip into a cup of water then it’s sure to sink
Step 2
We need to lower the paperclip extremely gently onto the surface of the water. The simplest way to do this is to take another paperclip, extend it out, and then use it as a lever to lower the paperclip that you want to float. (Make sure to fill your glass of water near to the top as that’ll make things easier.)
Top Tip:
It’s always a good idea to wash your hands with water only- not with soap - before you get started. More on why you need todo this in a sec!
Step 3
Sit back and relax and enjoy your floating paperclip!When you’ve finished doing that we’ll have a look at what’s goingon!
What's going on?
It’s all to do with density. The egg is slightly more dense that tap water (so it sinks
initially) but less dense than the salt water (so it floats on top of that). The reason
we’re able to put the egg in the middle of the glass is, as long as we’re careful, the less
dense tap water sits on top of the more dense salt water and they don’t mix together.
Warning!
tbd
Looking for yet more fun?
Continue the investigation like a real scientist...
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Does it have to be an egg that you use?
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What other objects could you try?