CERN

The first test of the CERN LHC happened today!! Check it out! Hear Brian Cox explain what it is for.

Welcome

Some of you like to find out in formation about their classes before they begin a new school year. If you are one of those people, then this is how you arrived here, I suppose. What would you like to know?

First Day of School

On the first day back at school you can expect to do a lab on position, time, velocity and acceleration.

Welcome Back to School Class of 2009!

Study Guide answers

.63 N, -1.3E-8 N, 1.6E-17N, 443m, 0.027 c, 1.7E17 e-, 1.6 E-4 F, 2.4 E=-8 F, 5.76E-7c, 6 9 3 5%, brown red yellow gold, violet gray yelow gold, 7 8 4 5%, 173000 Ohms, 2.3 E-6 A KCL, 3V.

Study Guide

I put a study guide for the electricity test on the schedule page. Check it out. I will put the answers on this page later.

test next tuesday and wednesday

Wednesday this week, 4/9/2008, we are looking at a variety of lab stations. These are to prepare you for the practical portion of next week's test. Try to be here, OK?

Finish Lab

Today in physics we will finish the Kirchoff's Laws Lab

Channel 11 Video

Here is the video from the news story on Physics Fair:

Electric Circuits

We are learning about electric circuits in physics. Circuit elements and electric current is the topic for today. Specifically Capacitors, which store electric charge.

Coulombs Law Sheet

Here are the answers for Coulomb's Law Sheet:

1) 0.63 N
2) 2.0 E 13 e- , 1.7 E 13 e-
3) 1.6 E -17 N
4) -3.2 E -26 N
5) 448 m
6) -1.27 E -8 N, Attractive, Opposite charges

Coulombs Law Lab

The Coulombs Law Lab link that I provided is missing a bit of the title so all you get is an error message. Add "tml" to the link URL and you will see what I intended. I plan to change it Monday. The real link is below

http://www.upscale.utoronto.ca/GeneralInterest/Harrison/Flash/EM/Coulomb/Coulomb.html

Monday Physics Fair

Hey, don't forget. Monday is Physics Fair in the Gym at Mounds View High School.

Third hour kids. Be here early (6:30 - 7:00 AM) to set up for Channel 11. They will be filming at 9:30 - 10:30 AM.

Due Date for PDR #4

What do you think of moving the due date for PDR #4 to Monday so you have another weekend to finish it?

Missing Tuning Fork

A tuning fork mysteriously vanished during sixth hour today. If you know of its whereabouts please inform Mr Washenberger.

OUT TODAY

Sorry Folks, I am out sick today, Tuesday, 2/26/2008. The sub has a copy of the worksheet for you and you can find it on my schedule page.
See you Wednesday, I hope.

Myth Busters

Check out the Myth Busters Rube Goldberg. They do a great description of how the project works.

ECLIPSE

It's 9:00 PM Wednesday, February 20. Go outside NOW and see the eclipse.

Test on Thursday

Be sure to prepare by completeing the study guide. You know where to find a copy.

Is it working?

I am having trouble with the animation to do the Two Point Lab at home. Anyone else having similar trouble?

Absent?

For those of you who may be absent today, check the schedule and refer to the wave notes. On the two point practice find all of the points of destructive interference. draw in the node lines and then use one of the equations to find the wave length.

Snells Law Sheet

Answers to Snell's Law Sheet:

1) 1.375, 2) 3.4 m/s, 3) 0.51 m/s, 4) 28 degrees, 5) 1.4, 4.07 m/s, 6) 15 degrees,
7) 4.9 cm/s, 3.75 cm/s 8) 17.3 degrees

Huygen's Principle

Check out the animations that show Huygens principle. They help you to understand how waves reflect and refract.

Traveling Wave refraction

Point sources and Huygen's Principle

Crest and Trough

If the crest is the top of the wave, the trough can be thought of as "the anticrest"!

Wave Sheet

Here are the answers to the wave sheet:
1) .62 m 2) 44 m/s 3) 5.2 Hz 4) 8.4 Hz, 27.7 cm/s 5) 1.65 cm .... 6) 0.5 m
7) (Yup) 8) 185 Hz 9) 1.45 m 10) 2.27 cm 11) 23.6 cm/s

remember the equations: v=f(lambda) and L = n/2(lambda)

mew or mu?

An experimental physicist performs an experiment involving two cats, and an inclined tin roof.
The two cats are very nearly identical; same sex, age, weight, breed, eye and hair color.

The physicist places both cats on the roof at the same height and lets them both go at the same time. One of the cats fall off the roof first so obviously there is some difference between the two cats.

What is the difference?

One cat has a greater mew.

Stroboscope!!!

The waves in the ripple tanks as I mentioned earlier can be studied by looking through a stroboscope (pictured at the left). The stroboscope allows the observer to "Freeze" the wave so that it can be more accurately studied.

Cold Out!

Researchers in Fairbanks Alaska announced today that they have discovered a superconductor which will operate at room temperature.

- 45 F is very cold!!!!!!

Ripple Tanks and Wave Properties

The classes are using the ripple tanks this week and next. These are great for observing a variety of wave properties. This week we see wave reflections from a variety of boundaries. Additonally, we will study wavelength, frequency and velocity of waves.

We have fifteen of these ripple tank setups so students have a great opportunity to participate in the activities.

Next week we'll see Snell's Law and two point source interference. To see an animation of what the ripple tanks more or less look like click on the link http://www.falstad.com/ripple/ and put the setting 1 plane source, 1 freq. in the second box.

Is anyone seeing this?

Hey, I am wondering if anyone is actually looking at any of this. If so, could you give me some feedback about that and if you have any suggestions?

I do have the notes from the last couple of days posted on the web. If you want to save writing in the next couple of days you could print out the notes and just bring them along to class. Then have them out as I go through and add any detail you might think is necessary. You can find the notes at: schedule
I have found that it works best in internet explorer.

Rube Goldbergs

I added a slide show you can see at the right. These are Physics Fair projects from last year.
Also, if you want to see some neat Rube Goldberg machines check out the links:

http://blueballfixed.ytmnd.com/
http://www.albinoblacksheep.com/flash/honda
http://www.break.com/index/best_rube_goldberg_ever.html

And, when you are on break.com, search Rube goldberg and check out all the things people have done to waste time! Keep in mind that even though dominoes and their likenesses are cool, they are very shock sensitive and not a good choice for Physics Fair.

Homework

You have probably noticed by now that the authors of the book round their answers to what they consider "sig Figs". Think about your results, do they make sense? How is your answer related to the authors answers.

First One!

This is my first blog entry. Its for a class I am taking called Web EDU. As a physics teacher in the information age, the popularity of blogs prompts me to get involved, so here I go.