Archive for January, 2009

Current Events: Volcanic Eruption

(CNN) — Mount Redoubt, the Alaskan volcano expected to erupt at any time, is getting a bit more edgy.

The Alaska Volcano Observatory said in a statement Friday “volcanic tremor” has increased in “amplitude.”

The activity on the 10,197-foot peak is “more energetic than that of the previous several days. However, it is still less vigorous than that observed last weekend,” the observatory said.

Peter Cervelli, a research geophysicist with the observatory, told CNN that “every indication is that we’re heading toward an eruption.”

Cervelli said scientists don’t know exactly when it will happen, but if it does happen, it could be days or weeks — or even hours.

“I would not be surprised to see it erupt at anytime,” Cervelli said. “We’re going to know it when we see it.”

Scientists raised the alert status Sunday to a “watch” level, the second-highest, based on seismic activity detected January 23.

The peak is about 100 miles southwest of Anchorage, the state’s most populous city.

Mount Redoubt last erupted nearly 20 years ago, in December 1989, and that eruption lasted until April 1990. Geologists think there could be an eruption “similar to or smaller than the one that occurred in 1989-90.” PopSci.com: Predicting eruptions

The 1989-90 eruption also spurred volcanic mudflows, or lahars, that flowed east down the Drift River. The ash fall was seen as far away as Fairbanks and the Yukon Territory border. PopSci.com: Prehistoric explosions wiped out ocean life — and created petroleum

The observatory has set up a Web camera near the summit of the volcano and another within Cook Inlet. It plans to do continuous visual surveillance, measure gas output and analyze satellite and weather-radar data.

FOR THE FULL STORY AND PICTURES: http://www.cnn.com/2009/TECH/science/01/30/alaska.volcano/index.html

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Davis Bombs

When I was down in Virginia visiting family, they shared with me this awesome new trick!
We started calling them Davis bombs, but I’m pretty sure I need to come up with a new name! Haha…

What happens is bits of tin foil are crumpled up to cover the bottom of a plastic bottle…we used anything from a small water bottle to a giant 3 liter soda bottle! Next, “The Works” toilet bowl cleaner must be poured into the bottle, just enough to cover the layer of tin foil. Seal the cap and….RUN!!

In a few minutes, the whole thing explodes with a tremendous BANG!!! 
We haven’t exactly figured out why The Works (found at Walmart) is the right solution, but I’m sure some Chemistry class somewhere would enjoy that fun project!
Enjoy!!!

Vacation Science: Hoover Dam

I was recently out in Las Vegas visiting my college roommate. My one tourism request was to see the Hoover Dam. My wish was granted and my friend and I hiked along Lake Mead all the way to the Dam. We went on the Power Plant Tour and saw the new bridge being built! It was very exciting :o)

The Power Plant Tour was excellent! We were privileged to see the generators at work as well as the massive pipes through which thousands of gallons of water flow through every day! We had excellent views of the Dam as well!! A new bridge is being built to allow the highway to bypass the Dam since the road passing over it winds through the mountains at 25 mph. The bridge was fascinating and promises to be one of the best views of the Dam!

The tour and museum were excellent educational resources. In the generator room, one of the generators was dissembled for maintenance – a phenomena that only occurs every 25 years! The rotor (the big wheel with large magnets attached all around) was just lying on the floor. It weighs almost 6 tons and took two huge cranes to move it from its normal location.
The museum also did an excellent job of explaining how the generators work! I have included pictures below to help explain:
This is a scale model of a generator. The water flows in the clear tube into the small dark green squares. These channels are openned and closed depending on the amount of water to be let in. As the water spins (sort of like a horizontal water wheel), the metal rod you can see in the middle of the picture begins to spin (this is the shaft). The shaft is connected to the rotor (the round part at the top which appears to have silver Lady Finger cookies attached) and the rotor spins as well. 
Surrounding the rotor is coils of copper wire. From Physics, we know that when we pass a magnet through a coil of copper wire (known as a solenoid) the magnet field changes. And where there’s a changing magnetic field, there’s current flowing.
So…to sum it up, the water makes the shaft and rotor turn, which causes the magnets to move past the coils of copper wire, causing a changing magnetic field, resulting in a current, or flow of electricity.
To top it all off — the Hoover Dam wasn’t even built to serve this purpose. It was created to aid farmers in irrigation and creating hydroelectricity was the only way to pay off such a massive project built during the Depression!!
I am seriously considering teaching Electricity & Magnetism units using the Hoover Dam so students can understand the real life applications!

Bill Nye

I have always been a fan of Bill Nye! At every opportunity, I use his work (via You Tube) for lesson planning! 

Well, I just hit the jackpot!!!
Bill Nye has a website with descriptions of do-it-yourself experiments and episode guides :o) The website is great! I did have some trouble getting in initially because I kept getting error messages that I didn’t have the correct system requirements, but I googled “Bill Nye Website” and found the second link to work!
Enjoy!

Vectors

I was teaching centripetal acceleration to my 10th grade sister several weeks ago. I used the race car on a banked curve explanation in another blog entry. We got to the end and she said something to the effect of, “Oh, I get it. That makes sense. Except — what’s a vector?”

I had to think for a moment. Outside of the physical science and mathematical world, what is a vector?
Finally I explained it as follows:
You’re having a picnic at the park. Just as you’re about to leave, you realize you don’t have any mustard for your hot dogs. So…you go to the store on your way to the park. Or…you could have just checked the back of the cupboard and realized you had some. Then you can just go straight to the park.
But the main thing is: you still made it to the park, right? So regardless of whether you stop at the store first, or not, you still have a picnic at the park.
My sister’s face lit up as she realized vectors were not the same as triangles (she’s currently in geometry) and she acknowledged that vectors and their resultant are all different ways of expressing the same thing.
Mathematically:
2+3+1=4+2=6

NASA 3D View: DAYS 2 – 5

For anyone who has ever considered taking this course, I highly recommend it! The class time is mainly a tutorial for the software, but it is well thought-out and I can not wait to use it in a class room :-)
I haven’t really written about my experience with the NASA 3D View course in the detail I wanted to, but here are highlights from the rest of the course.
ATMOSPHERE UNIT:
Students learn about fronts using NOAA satellite images and activities include weather forcasting. A great opportunity for kids to learn about practical applications.
LITHOSPHERE UNIT:
The highlight of this unit was the discovery of plates and fault lines by students. Students are provided with satellite images of the most recent volcanic and earthquake activity. They can observe this activity is clearly grouped over the fault lines. There is a cardboard & sponge activity where students can discover what happens when heavier and lighter plates collide. Two sponges and two cardboard rectangles are placed in a shallow tray filled with water. Students apply pressure from the outer two materials and observe what happens when the sponges and cardboard are pushed together!
HYDROSPHERE UNIT:
This unit had a lot of misconceptions — mostly that water underground is like a huge lake or river. One of the animations in the unit made it very clear how ground water moves through the dirt and rocks and into rivers and lakes. The animations are really fun and it is clear what is happening.
BIOSPHERE UNIT:
The initial misconception dealt with in this unit is what classifies a living thing. Many of the 3D images in the unit are of ecosystems where students can identify living and non-living things. Many opportunities to right these misconceptions. Another neat animation is a 3D tour of an animal and plant cell! Students discover what each part of the cell is responsible for.

NASA 3D View: DAY 1 The Atmosphere

Project 3D-VIEW [Virtual Interactive Environmental Worlds] is a truly interdisciplinary science curriculum for Grades 5 or 6. The program utilizes simple-to-use 3D technologies and is designed to increase student performance in science by building understanding of difficult concepts. 3D-VIEW is designed for adoption into the curriculum. 

For a tour of the curriculum, check out the website: http://www.3dview.org/tour.html

I have had the privilege of participating in this training through my connection with Columbia University Teachers College. I’ll be writing a summary of each class as
 blog entries.

The first class was all about the Atmosphere and used 3D graphics on a DVD program to show students realistic pictures of natural phenomena. The majority of the course is instructing us “students” how to use these materials as a supplement to classroom teaching. There is also a book with each unit that tells a story students can relate to. The atmosphere story details the journey of mountain climbers up Mt. Everest!!

One aspect of the Atmosphere unit that struck me as fascinating was a misconception addressed. Most students in grades 4-7 think air is made of no

thing and therefore has no mass! The simple experiment this curriculum suggests would easily tackle this misconception.

We can show air has mass by balancing clay on one side and a full balloon on the other side. pop the balloon and the ruler is now unbalanced!!!

When I searched online, I found this picture. When the two balloons are inflated, the rulers hangs parallel to the ground. When one balloon is popped (the sound can be reduced by poking through a piece of tape on the balloon). It is clear that a balloon filled with air is heavier than a balloon of equal size and (initial) weight.

Definitely check this program out and the other programs associated with the same organization! http://www.us-satellite.net/index.html