Facebooks

This week, a friend of mine sent me a pretty entertaining image via Facebook. Although Facebook is notorious for having the credibility of a fresh Wikipedia article, I recognized that the image was actually quite relevant to Physics:



One more thing; could the man in the image above, be related to our Republican hero here?




Jokes aside, I've finally caught up with the reading since missing a day due to a random cold. Momentum is a vector equal to mass times velocity, going in the same direction as velocity. As derived from Newton's laws, in a system with no outside forces (barring friction and air resistance), the momentum in a system remains constant. In our everyday lives, momentum is transferred quickly; in the collision of two objects, one will usually decelerate (or stop), and the other will usually accelerate. A common term today is the "domino effect," a "chain reaction" which occurs when a small change causes a similar change nearby, which then will cause another similar change." Most likely, this refers to a system of dominoes, in which as the first domino falls, the momentum from the fall transfers to each successive domino until the last domino, perhaps quite far away ultimately falls too

Now I don't have dominoes, but my mom's collection of Chinese dictionaries should suffice:





An interesting thing to note is that while momentum of the system supposedly should remain constant, certain books in the video clip appear to fall more quickly than others. The reason is that each book is its own system with different masses. Unlike dominoes which have uniform masses and should consequently should all fall at a uniform rate, the masses of my mom's dictionaries are different. If momentum is the product of mass times velocity, different masses should result in different momenta. The overall momentum of the system still obeys the law of conservation of momentum, however.

Being the conscientious scientist I am, I remembered to wear my safety goggles before performing any potentially harmful experiment (as always). Mocking me is completely unnecessary, Teresa.