December 2009
1 post
thank you for a wonderful semester
Since I am no longer teaching at Travis High School I will no longer be using this blog. But I wanted to thank the 34 students that were in my two classes for a wonderful semester. I’ve learned so much from all of you.
November 2009
15 posts
the wonderscope -- citizen scientists, it's your...
I just read on Seed Magazine’s daily zeitgeist that National Public Radio — the radio station that’s 90.5 on our Austin, Texas dial — has something going on called WONDERSCOPE where us citizen scientists submit a video on a science concept of their choosing. The first assignment/concept is TIME. You get EXTRA CREDIT if you make a video for this! Talk about how it shows...
Newton's laws from JR B-7
an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force.
EX. natural tendency of objects to keep on doing what they’re doing. All objects resist changes in their state of motion.
f=ma
EX. heavier objects require more force to move the same distance as lighter objects.
for every action there is an equal and opposite re-action.
...
May the Force be With You!- Newton's 3rd Broken...
Newton’s Third Law: The law of force pairs is probably the most familiar. It states that every force involves the interaction of two objects. When object A exerts a force on object B, object B also exerts a force back on A. The two forces are equal in strength and oriented in opposite directions.
EXAMPLE: A swimmer pushes off the wall of a pool. The swimmer applies force to the wall but her...
newtons 2nd law of motion from MM and SI
Newton’s second law of motion - the rate of change of momentum is proportional to the imposed force and goes in the direction of the force.
Types of friction:
Dry friction which is caused because of the movement of a solid surface over the other solid surface. It has further two types including static friction and kinetic friction. Secondly, lubricated friction which is because of two...
Newton's laws from AB
I. Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it. For Ex. If you push someone on roller blades there going to go forward and not stop.
II. The relationship between an object’s mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors (as indicated by their symbols...
METEOR SHOWER
photo from bbc website.
Tonight there’s a meteor shower called the Leonids. Read more here and here!
what happens when we add air resistance?
here is an extreme example of air resistance showing up in our normal projectile motion equations. Actually, this object is moving so fast and so high above the Earth that our equations need to be modified quite a lot — but you asked in class how things would change with air resistance… so here’s an answer.
can names be deceiving?
Sometimes names aren’t what they seem in science and mathematics. A case-in-point I will use here is an equation that you know very well: the Pythagorean Theorem. The theorem was well known and understood long before Pythagoras and his secret cult. Here’s a good page on it. Besides the equation being used in the west and mideast, it was also used in China around the turn of the...
gravity assist flyby
More on this later, but look at this gorgeous picture of Earth taken by the European Space Agency space probe Rosetta! It’s about to swing around the Earth in what is known as a “gravity assist flyby” — which means that the space probe will gain velocity (will accelerate) from the Earth’s gravitational field and be thrown off at a carefully calculated trajectory at a...
do you like your laws of motion with a donut?
Above is an image from the program for the homework assignment assigned Tuesday or Wednesday. It is located at http://www.ph.utexas.edu/~andye/newtonia/. This program explores… Newton’s Laws of Motion. More on Newton’s Laws can be found here:
Laws of motion from Rice Uni
and from Nasa…
Phet Simulation
LUNAR LANDER!!
Can you find better sites on Newton’s...
science action team
What keeps you continually questioning, seeking, finding, etc. etc.? For Jacques-Yves Cousteau — it’s all visible and spoken in his wonderful series documenting his adventures. They’re wild! And perhaps one of the best examples of a true ‘science adventure team’! And there’s a very strong sense that by using science and discovery we can learn how to make...
ArcAttack -- Singing Tesla Coils concert
Images from Wikipedia entries on Tesla Coil and Nikola Tesla.
The field trip on Nov 18th will be on Tesla Coils that can sing. See more info about the coils here: ArcAttack website. Also, find loads of pictures on flickr or search the internet for singing tesla coils, or play with ArcAttack’s Tesla Coil Emulator.
Find out more about Tesla coils here and here. More about electricity...
beauty in physics
Here are some pages from an astronomy text I’ve been looking at lately. It’s written by Petrus Apianus (German; 1495—1552). He was apparently the first to have discovered the fact that a comet’s tail points away from the sun.
Questions to consider when looking at the pages:
Do you find beauty in these pictures?
What do you like or not like about them?
What other...
....the true scale of the natural world....
This engraving is from a nice article in Seed Magazine. I like the idea of sticking one’s head through the outer spherical shell of stars and finding…. well, it looks like this guy found heaven.
The article linked above begins by talking about big numbers and how we’re kind of incapable of having an intuition about them. It then asks us to consider this:
We live in a...
October 2009
14 posts
u can't touch this; break it down
In class lately we’re dealing with vectors. If you want reminders on how to solve these problems, I learned a good trick from Mr. Wyman and MC Hammer. When we have a velocity vector in solving these problems, u can’t touch [it]… because u need to… break it down… into x and y components (he forgot to leave this last part of the lyrics out). You may not have...
playing with physics?
You judge for yourself. But I think these simulations are pretty nice. The first image simulates what happens with projectile motion while the second is on vector addition.
Images come from the PhET website.
what do i find inspiring?
these types of images
Images from Cassini mission at NASA
more found at The Big Picture
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WatchThis is a little outside the norm for either a science video or music video.
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"this really gave me the creeps"
Today I rediscovered radiolab (from WNYC). It’s an amazing radio show that has an intense and interesting curiosity about all things in the world, written and hosted by people that are similarly intense and interested.
A recent show told us about a video on… parabolas. See the video here. Sure some of the shapes featured are not parabolas, but it’s the intro when Steve...
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ingenuity and purpose
This story has been all over lately, even making it’s way on the Daily Show. A boy named William Kamkwamba in Malawi created a windmill (diagram bottom image) with limited information, limited resources but lots of purpose. The first image below is the windmill that he created! The second image is a diagram of the design, which is essentially a bike + bike dynamo being driven by the wind...
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consequences of our actions
What happens when too-loose environmental restrictions are coupled with a world that consumes far more than it needs? Stark images of pollution in China give some answers. More answers here and here.
Both photos by Lu Guang.
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martian spherules, hematite, and iron balls at big...
In August I went to Big Bend National Park in western Texas. It was full of too many amazing things for a four day visit. Our first night there I noticed a curiosity embedded in the rocks near our campsite (see image below). The little balls seem to contain iron (because of the coloring due to iron oxide). While watching an update on the Mars Rover mission, I was reminded of the...
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WatchI lived on a hill overlooking Gothenburg, Sweden this summer. On a very windy day I went outside and took hundreds of pictures seconds apart and put this together. Physics in action.
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let's kick up some moon dust
Tomorrow morning (Friday), around 6.30AM Austin time, two spacecraft are going to (purposefully) slam into the surface of the moon! This is part of a science experiment to analyze the chemical composition of the dust that lies in on the moon — specifically to see if there is water. The impact is going to be in a “permanently shadowed crater” that has been found to have a...
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demonstrations from today
This week we saw some of the properties of fiber optic cables and talked about CCDs. Both of these objects are the subject of the 2009 Nobel Prize in Physics. More can be found on the physics and prizes at the Nobel website.
The fiber optic cable has been known for over 100 years in various forms — not always useful. The first form talked about in the Nobel citation was as a “light...
the earth wobbles like a top
See here or see below for a nice visual depiction. Consequences of the wobbling (more technically known as precession) are: the north star, polaris, won’t always be the north star; the signs of the zodiac are always shifting (based on Greek times, when these things were first formulated, it’s off by one whole sign, so we’re actually a sign off from what newspaper horoscopes tell...