HEy there, I need some help. We have to build this thing for science competition and i have no idea at all how to do it. Can anyone help me please.

 

Here is the link: http://www.mrmaloney.com/nssl/events/2006-2007/0607_5-feb-yoyo.pdf

Your "yo-yo" can be up to half a meter wide, deep and tall and have a 6 meter "string". This gives you quite a bit of room to work with.

 

You can't light it up first so you'll need some kind of centrifugal switch that starts your lights from battery power. It needs to traverse the string slowly and the key there is that your "yo-yo" can change size once it starts. I'd use spokes which slip out easily (engaging your electrical circuit) and make it spin slower.

 

These spokes could be made from conduit (with stops to ensure they don't fly off) and then could be drilled with holes for the whistling effect.

 

Does that help?