Ohm's Law

Today we derived Ohm's Law using simulated data. You are expected to memorize and use Ohm's Law.

Due 3/31: HW: Resistance

Please answer on your own paper and turn it in. Due 3/31.

Resistance

Notes are below, and there is homework due tomorrow that will be posted in a separate entry.

Circuits and Current

Test 3

Good luck on your test! I will be back tomorrow.

Test 3 Review

Today and tomorrow we are reviewing for Test 3, which will cover mirrors, lenses, ray diagrams, and electrostatics. In addition to the review problems below, look back at bellworks, in-class activities, and homeworks. Especially these:

Lens ray diagrams
Mirror ray diagrams
The human eye
Static electricity
Coulomb's Law

From the book:
p. 478
15. a. What condition must exist for a converging lens to produce a virtual image?
b. What condition must exist for a diverging lens to produce a real image?
16. How could you demonstrate that an image was indeed a real image?
21. This problem asks you to draw ray diagrams to find the images created by three lenses. You will have to get these from the textbook.
p. 515
7. a. how do like charges behave?
b. How do unlike charges behave?
9. a. If electrons are rubber from cat's fur onto a rubber rod, does the rod become positively or negatively charged?
b. How about the cat's fur?
10. What does it mean to say that charge is conserved?
27. By how much is the electrical force between a pair of ions reduced when their separation distance is doubled? Tripled?
28.If you scuff electrons from your hair onto a comb, are you positively or negatively charged? How about the comb?
31. If a glass rod that is rubbed with a plastic dry cleaner's bag acquires a certain charge, why does the plastic bag have exactly the same amount of opposite charge?
35. The five thousand billion billion freely moving electrons in a penny repel one another. Why don't they fly out of the penny?
p. 529
14. Clearly distinguish between electrical potential energy and electric potential.
16. The SI unit for electrical potential energy is the joule. What is the SI unit for electric potential?
27. Is it correct to say that an object with twice the electric potential of another has twice the electrical potential energy? Defend your answer.

Bellwork 3/18 - 3/23

And another page bites the dust...

Circuit Lab I

Electric Potential Energy and Electric Potential

No homework tonight; have a good weekend!

Coulomb's Law practice

Here's what we did in class today. You must turn this in on a separate piece of paper. This is worth a lot of points.

Wednesday, 3/18: Coulomb's Law

Today we derived Coulomb's Law (or at least the proportionality version of it). First, the bellowork:



Now, the assignment:


And the data table with some conclusions:

Bellwork 3/2 - 3/16

Behold! Another page of bellwork is filled!

Due 3/17: HW: Conservation of Charge

Answer the following questions on your own paper:

1. Why do a balloon and a piece of fur attract after you rub them together?
2. Why does a charged balloon stick to the wall/ceiling?

Be extremely thorough. These two questions, with diagrams, should take up a whole page.

Monday, 3/16: Charging by Friction and Polarization

Notes below; don't forget to do the homework!

The Lost Week

Hey folks, sorry about being out sick last week. We'll pick up again starting tomorrow.

Friday, 3/6: Electrostatics Intro Lab

Thursday, 3/5: Vocabulary Cards

Today we're taking a break and reviewing some of the vocabulary words from the last few weeks. This assignment should be taped into your notebook on a left page and shown to the teacher to check off.

Cut a page of notebook paper into at least five pieces. Make 5 vocabulary cards, choosing from these words:

convex
concave
converge
diverge
scale
lens
mirror
focal point
Focal length
real image
imaginary image

On the front of the card, draw a picture that represents the word. The picture must have at least 4 colors and there should not be any writing.

On the back of the card, write:
1. The word
2. The definition
3 A link (a word that reminds you of the vocabulary word)
4. A sentence that uses the word

This is due tomorrow, Friday March 6th.

Wednesday, 3/4: The Human Eye

Today we talked about the human eye from a physics standpoint. There are many, many more things you could learn about the eye, but we are only covering near and farsightedness, blind spots, and the iris. Below are the notes pertaining to nearsightedness and farsightedness.

Your homework is to answer this question on your own paper:

What does it mean to be nearsighted or farsighted? How can this be fixed?

Tuesday, 3/3: Mirrors and Ray Diagrams Continued

The subject of mirror ray diagrams continues today. For the second half of the period, we worked on two practice problems. There is also homework. The practice problems, homework, and notes are below.

Monday, 3/2: Mirrors and Ray Diagrams

Today and tomorrow we are going over the ray diagrams of mirrors. Notes below.