EM Induction e-Learning: Going into next week

Happy Friday, everyone! I do hope everyone is doing OK, as we have been out of school for a full week. Remember counselors, social workers and school psychologists and nurses are available as isolation continues into the foreseeable future. As you've been doing, keep each other entertained and in contact virtually, and look out for each other!  😀

Please be signing in with the school each week day. 

Now that we know AP Exams will be held, but in shortened, online form, for us that means just the 'E' in "E&M,' and only 45 minutes. More details will follow as we get confirmed reports to the school.

Next week we will focus on the second version of Faraday's law, which is in Packet #3. This is when things are not moving, and we have a constant area but changing B-field:  emf = -A dB/dt.
For this case, because there is a change in magnetic flux, there is still induced voltage, currents and forces on the wires. But physically, there is no longer motion, so F = qv x B does not explain why and how the current starts in the wire loops. Instead, there will be an E-field that is induced, or turned on, whenever the B-field changes.

The relevant videos for the AdB/dt type situations are: 
- a case of B-field changing and the induced emf in a circuit
- induced, circulating E-fields when we have dB/dt
- Maxwell's displacement current...finishing off the laws of E&M (how capacitors really work!)

We will go through the AP problems in Packet #3 as practice. We will start several of them together to get going and go over the key concepts, and some can be used to get some practice. We will also use a video to get some graphics for how light itself works! It is an electromagnetic wave, where changing E-fields and changing B-fields induce each other in order to produce a wave in the fields!! Weird, but also really cool!

The very last thing for your high school physics career will be in Packet #4, on inductors and circuits with inductors, including the guts of wireless technology! Also, a little bit about transformers, power plants, and how the power grid is set up. More on that later.

In honor of Friday, an oldie but goodie (???):