Test myths without leaving the comfort of your home. Find out if it's possible to put a pin through a balloon without popping the balloon and if air can be weighed without the aid of sophisticated devices. Does warm water freeze faster than cold water? The answers to all of these questions can be found here.
Collecting fingerprints
Ever wondered how to collect fingerprints? It’s easier than you think. All you need is a sheet of paper, a plastic-covered book, talcum powder, a lead pencil, and a sharpener. Professionals use activated carbon to identify fingerprints, but you can easily replace the activated carbon with the lead powder that remains after a pencil has been sharpened or by using plain talcum powder.
1. Make a fingerprint by pressing a slightly moisturized finger on a piece of paper or plastic-covered book.
2. Next, collect the particles of lead from a sharpened pencil.
3. If you’re using a piece of paper with a white or transparent surface, sprinkle some of the sharpened pencil’s lead powder over the surface. If the surface is dark, sprinkle talcum powder over it.
4. Carefully lift the paper or plastic-covered book and gently shake off the excess lead or powder to display the fingerprint.
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