Week of April 9, 2018

Remember to read past the Cool Science of the Week to find your assignments. 🙂

Cool Science of the Week
We’ve discussed satellites and the relationship between tangential velocity and the gravitational force that creates the centripetal force. What happens when a satellite’s tangential velocity slows so that the centripetal force it requires is less than the gravitational force it’s experiencing? It falls back to Earth, and this is precisely what will happen with the Chinese space station, Tiangong, sometime during spring break somewhere between 43 degrees north latitude and 43 degrees south latitude. (Yes, we are in that range, but only at the high northern end withour 41.5 degree latitude.) Not to worry: Most of the school bus-sized space station will burn up due to friction upon reentry, and the chances of being hit by what’s left are infinitesimally small. Why is this happening? China lost control of Tiangong in 2016, so it cannot force a controlled landing. This is one of the risks of our space station/satellite age, and it gives you the chance to ponder risk versus benefit, one of the most important questions in science and technology! Definitely check out this link, which drives home home the understanding of just how much “stuff” we’ve put in orbit around our planet. Fun fact: The Chinese space station featured in the movie Gravity is a future version of Tiangong, since Gravity is set in the near future. Chinese scientists even got some ideas from seeing the movie! Fun link: How to track the space station’s spectacular reentry
FILE - In this Nov. 3, 2011, file image taken from video from China's CCTV via AP Video, China's Shenzhou-8 spacecraft is docked with the orbiting Tiangong-1 space station. China's defunct and believed out-of-control Tiangong 1 space station is expected to re-enter Earth's atmosphere sometime in the coming days, although the risk to people and property on the ground is considered low. (CCTV via AP Video, File)
Image from Cleveland.com

This Week in Physics
First and foremost, remember that we have the SLO on Wednesday, April 18, which is the week after we return. It’s in your best interest to start studying early. It covers units 1-6, and we will spend some class time reviewing. This will impact the rate at which we are able to move through our new unit. Ideally this week we will complete assignment 1 from unit 7 and take a quiz over goal set 1. If we are lucky we will take notes on PODCAST 2: Electric Force (Coulomb’s Law) and begin to move through that material. I’ll make announcements in class in regard to due dates.