Study Guide Day!

Today is your day to work on your study guide. It is unit 3 for conceptual and unit 2 for honors. Below you find pictures of the back of the study guide and the abridged answers. Test tomorrow!

Lens Lab

Today we are completing your Lens Lab (see yesterday's post). You will also receive you study guide for your test on Tuesday. Monday will be a work day.

Lens Lab Setup

Today we got ready for the lab we are doing tomorrow, shown below. If you have long hair, please bring something with which to tie back your hair; we will be using candles and I do not want your hair to get singed accidentally.

Conceptual: Reflection and Refraction Practice

The was no bellwork today so that you could have as much time as possible to work on missing assignments or Reflection and Refraction Practice. This is a lot like your test (which is next Tuesday) and is due tomorrow.

Honors: Reflection and Refraction Practice

First, a little more about the eye and how nearsighted and farsighted vision works.

The rest of the day was yours to work on Reflection and Refraction Practice. Make sure you got the Honors version. This is due tomorrow.

Honors: Lens Ray Diagrams II

 Today we finished the notes on lens ray diagrams. Tonight's homework is Concept-Development 30-2.

Conceptual: The Eye

No homework tonight!

Honors: Lens Ray Diagrams I

Today we started drawing lens ray diagrams. We will finish these tomorrow. Homework tonight is Concept-Development 29-4. This is NOT the same Concept-Development 29-4 that the regular classes already had. Make sure you get the right one.

Conceptual: Lens Ray Diagrams II

Today we finished learning how to draw lens ray diagrams! Homework is Concept-Development 30-2.

Conceptual: Lens Ray Diagrams I

Today we started drawing lens ray diagrams. We will finish these on Monday. No homework tonight!

Honors: Lenses

Due to the pep assembly today, we were missing about half of the students. Therefore we did not have bellwork. We had time to work on yesterday's lab and fill in these notes about lenses:

No homework this weekend. Bring a ruler and three different colors of writing utensils on Monday.

Conceptual: Lenses

First we used bellwork to make last night's homework a little more clear.







Then we used our light sources and some small plastic lenses to discover how convex and concave lenses affect light.

No homework tonight!

Lens Lab: Real Images - Part 1

Today we are starting a lab, but we won't get all that far. First, some bellwork, during which we found out that the place where an image forms behind a convex lens is the focal point IF the light coming into the lens is parallel. The light will be parallel if the source is very far away.



So we took some lenses, looked at a distance source of light (outside), and measured the focal length for our lab. We will continue this tomorrow; please fill out the values of d_o based on the focal length of your lens.

Lens Lab: Real Images

Day two of the candle lab! First some bellwork:



Then we turned off the lights, lit some candles, and took some data! Your lab sheet is due tomorrow.

Lens Ray Diagrams

Today and tomorrow we are learning to draw lens ray diagrams.  Honors, you started yesterday and finished today.

Homework: Concept-Development 30-2

Lens Ray Diagrams II

Today we finished up the notes for lens ray diagrams and started working on your homework, Concept-Development 30-2.

Ray Diagrams

Today we learned how to draw a ray diagram. Here are some notes from last year:

Ray Diagrams I
Ray Diagrams II

No new homework tonight.

Lenses

Today we are working with some things that use refraction: lenses. First, the bellwork:



We then used our light sources and some lenses to find out what each kind of lens does to light. I'll get a picture of our final notes later, but for now, just know that convex lenses converge light and concave lenses diverge light.

The rest of the period we spent working on Concept-Development 29-3, which is due today. No new homework tonight for regular classes. Honors Homework: Snell's Law was assigned for honors students.

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.