Knots: Friend or Foe?

Knots affect our lives in perplexing ways. They can perform life-saving assistance, such as during rock climbing, or provide Sisyphean puzzles of entanglement. Often, knots seem to have the contrarian personality of an adolescent. They loosen and unwind when you want them to stay fastened, and inevitably form tangles of confounding complexity when you seek to avoid them. These puzzling characteristics of knots were brought to mind when I read two recent articles about the scientific investigation of knots.37190697-May-5-Darcia---Option-2

Why Knots Fail

The explanation of how shoelaces come untied, published in Proceedings of the Royal Society A, was quite prevalent in the news cycle recently. After observing slow-motion video footage of the shoelaces of a runner on a treadmill, researchers were able to explain how motion affects knots and results in untied shoelaces.

First, they observed that the failure of a knot is not a gradual process, but happens abruptly over the course of only one or two strides. This is possible due to the surprising amount of force generated by the impact of one step, which this study calculated to be an average of 7 g—more than twice the g-force experienced by the Space Shuttle upon reentry into the Earth’s atmosphere. Continue reading “Knots: Friend or Foe?”

Harnessing the Power of Play to Keep the Lights On

My daughter is just shy of one year old and, now that she’s walking, we’re getting increasing glimpses into the active little toddler she’s going to become. Heaven help us. I think most adults marvel at — and sometimes lament —  the enviable amounts of endlessly renewable energy kids expend every day, but I’d never really thought of them as being an actual source of renewable energy until I read an article about playground designs that harness the energy of children’s movements and turn playtime into power, with fascinating and technologically compelling results. Here are a handful that I thought were super cool: Continue reading “Harnessing the Power of Play to Keep the Lights On”

Getting Our Hands Into Some Good Ol’ Home Science

static_detection-simple_electroscopeFor many, this time of year brings with it the opportunity to enjoy a bit of holiday fun with kids. In fact just recently I had the chance to spend a day doing several home science activities with my four- and seven-year old boys. All were simple to set up using commonly found household items in a way that was both instructive and rewarding. Continue reading “Getting Our Hands Into Some Good Ol’ Home Science”