The Physics of High Heels
Did you know that a 110lb. woman wearing stiletto high heel shoes puts a lot more pressure on the ground than a 6,000lb elephant? Learn what high heel shoes have to do with the laws of physics that XVIIth Century physicist Isaac Newton derived. Also, what makes one high-heel shoe more comfortable than another? Is a thicker heel always better than a thinner one for high-heel shoes? How close approximately should the heel be placed away from your toes? What gives a woman the best support and dynamic leverage in her walking style? Why are some surfaces better than others for walking on a high-heel? Does leather always stretch? And are some materials better for constructing a supportive heel? We will talk about the best ways to choose a high-heel shoe and the mechanics of walking and supporting your body in a safe and stylish fashion.
Time-reversal is the process whereby a signal is emitted by a source and propagates in a medium with scatterers in it. The waves are recorded at a receiver over a time much larger than the original pulse duration so as to capture the multiple scattering. The receiver then reverses the waveform in time and re-emits it into the same channel. The waves back-propagate through the medium retracing the multiple scattering paths taken on the way to the receiver and ultimately refocus at the original source location in space and time. Time-reversal in an enclosure with a single detector achieves spatial focusing of the acoustic energy to within one half of a wavelength of the initial sound signal. For my Ph.D. Dissertation I studied the phenomena of time compression and spatial focusing of time-reversed acoustic signals in closed environments with strong reverberations.
Emergent behavior is when a system made up of individual parts forms more complex behaviours as a collective, and exhibits properties, which the individual components themselves do not have. We are familiar with this concept in biology and social networks. For example: neural networks, popularity, traffic jams, etc. We need a large community of people for the concept of popularity to arise. Just like you need a large number of cars for a traffic jam to form. Emergent properties arise when a complex system reaches a combined threshold of diversity, organization, and connectivity. The interesting thing about these phenomena is that one couldn't explain them by only focusing on understanding the independent behavior of each component. In essence emergent phenomena phenomena arises only with a large number of parts in the system, and when the relationships between individual particles generates new properties. In physics, however, there is often the tendency to believe that the universe around us will be clarified by understanding how every single part behaves. Some would call it a "Theory of Everything" But the answers are still elusive, and we are yet on a quest to unify the three high-energy forces electromagnetic, weak and strong with the 40 orders of magnitude smaller force of gravity.
There is nothing wrong with this reductionist approach. But perhaps we cannot deduce all of the fundamental laws of nature from individual particles. Maybe, as some propose, the Total is More than the sum of its parts.
Would you leap 30 feet in the air into a small kiddy pool? Seem humanly impossible? Think again.
On National Geographic's Humanly Impossible TV show, Dr. Berebichez and a team of scientists and doctors explore the science behind extreme performers such as glass eaters and sword swallowers and how they push the human body to extraordinary limits. But how do they do it? Watch these videos to find out more.
Think you could lift seventy pounds? Think you could lift seventy pounds with your nipples? The Great Nippulini can.