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Tuesday, October 17, 2017

Classes for today

Periods 3-4, 8-9:

If any brave souls can volunteer and put up their solutions for the E-fields on the NON-uniform density problems from last night, let's see if we can reach consensus. Remember, these are worst-case Gauss scenarios.

Then there is the reality that not all things we use in electronics are spheres, long cylinders or large plates. There are rings, wires that really do have ends, and so on! You know where this is going....NON-Gauss situations. Check out videos on how we try to approach real objects such as the E-field for charged sticks we used in lab before, as well as finding the potential for a stick.

When done, please work together and try the problems on pages 2 and 3 of the NON-Gauss packet that will be passed out. On the stick problem, page 3, also try to find the potential at the same point shown, in addition to the E-field.

Period 6:

Let's pull out your Chromebooks, and check out a Khan video on the types of problems we are starting to try and solve, those with acceleration. Anything we do with constant acceleration will use the three formulas on the sheet we got yesterday. For any type of problem like this, it is a good idea to list out the information we are given in a problem, such as distance traveled, initial speed, final speed, the time traveled, and the acceleration value. Some of these will be known, and one or two not known in any given problem - but we have the three sets of relationships that will help us out, so we can find any of the unknowns.

So watch a video on how we can do this to try and figure out the acceleration of a plane launching off an aircraft carrier. Take notes on it. This will be a guide for doing the couple problems on the third page of our packet from yesterday. After watching the video, try the problems with one or two classmates, and have them ready for Wednesday. These will be typical, everyday sorts of situations that we can use the three equations over and over and over again, to predict what will happen when acceleration is involved.

Wednesday, October 4, 2017

Nobel Prize in Chemistry Announced this morning!

The Nobel Prize for chemistry was given to three scientists this morning, for their work and creation of cryo-electron microscopy. They are an American, Joachim Frank; a Swiss, Jacques Dubochet; and a Brit, Richard Henderson. Their work and revolutionary imaging has helped make high-resolution images of biomolecules in action.These images are also 3-D, moving away from old 2-D imaging techniques. Researchers can freeze molecules in mid-movement, providing snapshots of complex processes so they can be understood with entirely new levels of precision. This should help in drug treatment development, studying aging, addictions, cancer development, and so on. Very cool, literally and figuratively! :-)

Tuesday, October 3, 2017

Are we going to be able to see black holes? Perhaps soon!

While black holes cannot be directly seen, since light cannot be emitted through the event horizon of the black hole, it may be possible to see the so-called accretion disk, a hot, rotating region of hot gas and plasma that is trapped by the gravity of a black hole, and which could come from the immediate environment as well as a companion binary star near the black hole. There is some new telescope technology that should be able to see accretion disks, and this new experiment is called the Event Horizon Telescope. This tool, along with the rapidly growing field of gravitational wave detectors like LIGO and others that are being built, could be opening the door to a new branch of astronomy that complements astronomy with electromagnetic radiation.

Nobel Prize in Physics - LIGO and Gravitational Waves!!

Congratulations to three Americans who won the Nobel Prize in Physics, 2017, for their pioneering work in testing and confirming Einstein's general relativity prediction of gravitational radiation! The Nobel committee recognized Kip Thorne, Rainer Weiss, and Barry Barish for their efforts in creating the LIGO experiment. BTW, a key senior scientist on this experiment is NU professor Vicky Kalogera.

2017 Nobel Prize in Medicine & Physiology

Congratulations to three Americans, who were recognized by the Nobel committee for their work in understanding our biological clock, and what makes our circadian rhythms so vital to our lives! They are Jeffrey Hall, Michael Rosbash, and Michael Young.

Tuesday, September 12, 2017

Understanding Matter and Forces: Standard Model

The Standard Model is the name of the theory we use to help us understand what makes up the universe (i.e. particles of matter) and how matter interacts (fundamental forces of nature). It breaks down the hundreds of particles in nature down to 6 quarks, 6 leptons, and a few force carrying bosons, along with the Higgs boson that provides mass to particles in the first place. Check out a summary video!

Big Bang - Start of our Universe

What is the Big Bang theory for the creation of the universe? In principle it is as easy as saying there was a large explosion of unimaginably hot energy, which 'cooled' to form the fundamental particles and forces that we see in the universe today. This happened about 13.7 billion years ago, according to present-day best measurements and calculations.

As with any scientific theory, no one should put any belief into it until there are predictions made from the theory that are then tested experimentally and through physical observations. Over the past 100 years, the theories of Einstein and the eventual Big Bang models have gone through this slow process, and confirmation of the key ideas have occurred, making this the best understanding we have for the universe's creation.

Check out this video that explains the gist of the Big Bang theory, and a couple reasons why scientists believe it is a valid theory. Check here for a quick example of the Doppler effect.