Science: Technoquest

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Q Why don't woodpeckers get headaches?

Woodpeckers have fluid surrounding their brains. They also have very large skulls and small brains - with not much momentum on impact. They also have shock absorbers in the junctions between their beak and skull.

Plastic is made by a process called polymerisation. This is where chains of molecules (made up mostly of carbon and hydrogen atoms) are stuck together to make very long chains of molecules and networks. The raw material the chains of molecules come from is usually coal.

Q What is Russian multiplication?

Russian or peasant multiplication is multiplication by repeated doubling. For example, to multiply 17 by 13 you double the 17 and halve the 13, and add the doubles that correspond to an odd number in the other column. Like this: 17 x 13 - doubled and halved: 34 x 6 (add 17); doubled and halved: 68 x 3 (add 68); doubled and halved: 136 x 1. So the answer is 136 + 68 +17 = 221. It's a handy way of writing long multiplication in binary.

Q How do cats purr?

Recent research suggests that in domestic cats its the vibration of an elastic ligament linking the clavicle bone to the throat - which creates a purr during both inhaling and exhaling. In their larger cousins, things are slightly different, restricting the purring to an out-breathe only. Neither kind of cat ever stops purring - they just control the volume - with loud purrs conveying anything from anger in a Snow Leopard to contentment in a Tabby!

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