Archive for November, 2008

Science Blogs!!!

Just found this blog for Science and Math teachers which focuses on free resources!!!

Check it out:
Another blog is for parents and caregivers: 
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Vocabulary Pictures

I was chatting with my cousin at a family gathering today and asking her questions about the Physics class she’s currently taking (she’s a 9th grade student). She mentioned on homework assignment that got me all excited!!!

As a test is approaching, the teacher gives each student a list of vocabulary words. The students are responsible to “surf the net” and find pictures they can use to illustrate each word. The same picture can be used for each word, as long as the student can skillfully explain the connection. 
I think this is a great way to get kids thinking about Physics in their everyday lives and a creative way to get them out of the textbook!!
Never mind the fact that it is a useful assessment tool for teachers. I’m sure this teacher can easily tailor his exam reviews based on the kids’ assignment answers!!

Citigroup is Falling Down

No, I don’t mean the company is falling apart due to the economic crisis of 2008…

I read recently in the book Einstein’s Refrigerator, a story about the Citigroup Center building in Manhattan (the building pictured to the right with a triangular roof). The book, compiled by Steve Silverman, is a collection of believe-it-or-not stories “from the flip side of history.”

In the Citigroup story, a college student from New Jersey calls the engineering firm responsible for the building, claiming a flaw in the design poses a much larger threat than anyone realizes. Out of curiousity, the chief structural engineer William LeMessurier looks at the plans and does some quick math. He finds that the design leaves the building at a 40% increase in stress if hit by a quarterly wind. However, he learns the on-site engineer decided to bolt the structure together instead of welding (as the plans dictated) and t
he math under that circumstance showed an increase in stress by 160%!!!
The other problem was the fact that one corner of the building hung over St. Peter’s Lutheran Church. You can just barely see the church in the left bottom corner of the picture at the rig
ht.
To make a long story short, Citigroup wanted to keep this huge error in engineering on the “down low”, so all the work done to fix this problem was done in the middle of the night. No one ever knew the building was being fixed and strengthened while they were sleeping!
No one knew, but people wondered why there was a glow near the Citigroup building every evening. LeMessurier even got a call from the New York Times at one point. Lucky for him, they went on strike that very evening!
So, needless to say, the Citigroup building is safe now. If it had ever fallen over, the Red Cross estimated it would have caused 156 city blocks worth of damage! That’s almost the whole of Manhattan!!
I share this story, because it is a great way to use current events to teach Physics! The main issue of this problem is the building’s center of mass and more specifically loads and torques. Students might enjoy doing the calculations LeMessurier did and determine the safety of the building themselves. Below is a quick description of the building.

 

Great Website: Engineer Your Life

My mom recently showed me the website below. So cool! I’m just disappointed the website doesn’t have any teacher resources…but it’s great nonetheless!

Check it out —> http://www.engineeryourlife.com

Evolution Activity

So I observed David McKinney, an 8th Grade Science teacher at Isaac Newton Middle School, today. It was really exciting to see all his energy — even if he admitted part of his energy high was due to having observers in the room! He did the following activity with his class and it was so fun to watch, never mind that the kids could see evolution (a change in frequency of a species) in action.

Based on Sir Charles Darwin’s research in the Galapagos Islands, the kids were challenged to see which finch beaks (modeled with tweezers, clothespins, toothpicks, and spoons) were most effective in eating which foods (rice, sunflower seeds, marshmallows, and marbles). At first, the kids had a plate representing an island since Darwin found there were entirely different species of finches on the islands in comparison to the mainland. Each student made a prediction as to which “beak” would be the most effective. Then they emptied a bag of food onto the plates (each bag had an assortment of the “foods” listed above). They were given 10 seconds with each “beak” to see how many pieces of food they could collect in a cup: NO SCOOPING WITH THE CUP ALLOWED! Results were recorded in a chart and organized by the type of food.

The second half of the activity was based on the first. Half of the groups were given a bag of rice and the other half a bag of marbles since their respective islands had a drought of the other food. Kids predicted which beak would be most effective in this case. Each beak had 10 seconds to prove itself and the data was recorded.

McKinney ran out of time at the end of class, but they had a short discussion about why certain beaks were advantageous given the indigenous food supply. It seemed empowering for the kids to participate in an experimental activity similar to the acclaimed scientist Darwin that it is associated with!

**I later found out this activity is a state mandated lab activity for the Regents. Another variation we did in class was to have students sift “food” through a paper plate with holes in it.

Atomic Humor

Two atoms were walking across a road when one of them said, “I think I lost an electron!” “Really!” the other replied, “Are you sure?” “Yes, I ‘m absolutely positive!”

Pendulum Conundrum

A classmate and I were mulling over pendulums on the train ride last night and couldn’t come to any conclusion. We were discussing how mass as a variable effects two pendulums. Initially, my response was that a more massive pendulum would rise to a higher point once released (if two pendulums of differing masses were released from the same height) because it has greater PE, but then we got confused because it also takes more energy to keep it swinging. So then it also made sense for both pendulums to reach the same height and have the same period with every oscillation.

Since we couldn’t come to any conclusion, I went home and played around with some homemade pendulums. I constructed one with some gift wrapping ribbon and one fork and another with gift ribbon and five forks. Attached is a slide show and commentary of what I found. I pretty much observed both phenomena of the two forks at same heights with same periods as well as two forks with same periods but different heights. Then I coupled the two pendulums just for kicks.

My husband Keith got home from work as I was curled up nearly under the sink in the bathroom trying to take pictures. Oh, Physics!