Spark Analysis Guide

Answer each question using analysis from the video.

Link to video

https://www.youtube.com/watch?v=Gtp51eZkwoI

In this video has 3 parts, but listen only part number 1 to answer all of these questions.

Questions:

1. How has the term "Electrician" changed between the early 1700s and today?

2. What does that change in meaning tell us about changes to the scientific approach to studying natural phenomena?

3. Professor Al-Khalili calls Davy's arc light "the end of one age, and the beginning of another."

• What were the "ages" to which he was referring?
• Why do you think he chose that particular event to mark the change?

4. Today we use the terms "volt" and "voltage", but they are not the same thing. What is the difference in their meaning? How do we use each of these words now?

The era that coincided with the European Enlightenment also saw theglobaldevelopment of sound scientific methods that all good scientists strive to follow. You have likely been presented with one or more summary versions of this process that should look something like this:

1. Ask aQUESTION
2. ConductRESEARCH
3. Make aHYPOTHESIS(a logical prediction with reasoning)
4. Design andcarry out anEXPERIMENT
5. Record yourOBSERVATIONS
6. DrawCONCLUSIONS
7. COMMUNICATEyour results It is alsoabsolutely necessaryfor good science to follow anITERATIVE PROCESS.That process is recursive in nature, which is to say that it repeats itself. So, we should add the following steps:
8. UPDATEyourMODEL
9. Ask a newQUESTION...

The most important feature of the iterative process is that it never really ends. Each of us carries on the work of scientists who came before, and we, in turn, will pass on what we have learned to the scientists who follow after.

Having a good mental model is an essential part of this process. That model will always have a mental component - WHAT we think is happening, and WHY - but may also have a mathematical component (mathematics is, after all, the language of science) or maybe even a physical one that we build. Understanding, testing, and improving that model is the heart of the iterative process.

5. Musschenbroek's development of the Leyden Jar followed this process. He hoped to collect charge in the jar like a liquid and store it for later use. In his initial experiments he did something that we now know caused his experiment to "fail" (i.e., no charge was stored in the jar); he placed the jar on an insulating disk of wax while attempting to charge it. What made that action consistent with his model? Or, in other words, what did his model predict would happen if he did NOT place the jar on an insulator, and why?

6. Why did news of the Leyden Jar have such a tremendous impact around the world?

7. How did the Leyden Jar change people's mental model of electricity at that time?

8. Franklin and Volta profoundly changed the models of electricity shared by scientists in their times, by showing that the static electricity created by early electricians was the same as the electricity in Lightning (Franklin) and as that found in animals and even humans (Volta). How did the discovery of theelectronchange our understanding from the "Franklin Model" of electricity?

9. Luigi Galvani's ideas of "animal electricity" were shared by many, but his experiments were not always consistent with his model.

• According to Galvani's model, what would have been the problem with removing the frog's head before conducting his experiment?
• With this model, what should he have expected to happen?

10. After Galvani's later experiments with two types of metal wire and no source of electrical potentialstill caused the frog to move, what part of the iterative process did he fail to follow?

11. After hearing about Galvani's frog experiment, Volta followed the next steps in the iterative process. Based on Galvani's experiments, Volta thought of more questions and did further experiments. What happened as a result?

12. What does it mean to make the scientific process iterative? Why is that important?

13. From the material in this video, please summarize below your best understanding of electricity and how it works. You should include descriptions of the following:

• what electricity is,
• where it comes from,
• what can be done with or to electricity, as well as
• what it needs in order to do those things.

USE THE VOCABULARY you have learned so far and use the work you have done so far to make your summary.

Note that this question is worth a lot of points; make sure your answer appropriately reflects the higher value of this question.