Happy Valentine's Day--seeing hearts

Here's a really cool video that shows just how much we are pattern seeking animals. We can find hearts anywhere.

You CAN change the world

Never doubt that a small group of thoughtful, committed, citizens can change the world. Indeed, it is the only thing that ever has.

--Margaret Mead

Boy, 7, raises $240,000 for Haitian Relief.

Projectile Motion - 1/19/10

There are multiple concepts that come into consideration when discussing Projectile Motion. Recently, our class (period 1/2) discussed Vertical Velocity (VY), and Horizontal Velocity (VX).

A projectile's horizontal velocity is constant, and has an acceleration of 0. This is due to the fact that there are no substantial forces acting on the object in the horizontal direction. The only horizontal force acting on the object would be air resistance, and in most cases, this force is negligible (i.e. a small steel ball). Because V(sub X) is constant, it's initial velocity is the same as its horizontal velocity at any point in time (unless the object has stopped).

A projectile's vertical velocity has constant acceleration. The earth exerts a gravitational force upon the object that pulls the object towards the earth with a constant acceleration of about 10 meters every second. This is why the object eventually stops moving (in general). The earth's gravitational force brings the object towards it. and the object eventually hits a surface that stops it's motion.

Backyard Ballistics Packet

Here is the reading from backyard ballistics that will tell you how to build a tennis ball morter, catapault, or potato cannon.

Backyard Ballistics

Class on 1/7

today in class we focused a lot on the concept the force of gravity on any two objects will cause them to fall at the same time, despite weight or mass differences.This is because gravity will only exert as much force on and object as it exets on the earth, by having mass orweight. So a light object falling will only exert a small force on the earth, and will only get or require a small reactional gravitational force to make it fall. For a hevy oject, this is true except that it will exert more force on the earth and thus require a greater gravitationl force to be exerted on it. But the objects will fall at the same tie because the gravitatioal forces are different, because the heavier object requires more just to fall at the speed of the light object
Also, we rached the concuion that dropping and object and throwing the same mass object from the same height, without upwards trajectory will result in both object hitting the ground at the same time. Thisis because an objects horizontal motion wil nt affect its vertical motion, so the thrown object will fall at the same time as th oher ball which is dropped, no matter how fast it is going horizontally

Burj Dubai Base Jump

Two basejumpers just set the world record for BASE jumping from the world's tallest building the Burj Khalifa (formerly called the Burj Dubai), from a height of 828 m.

Check out the video below:


Two questions:
1. Why didn't this video take the 13 seconds you calculated take an object to fall to the ground?
2. What was the average velocity of the skydiver? How does this compare to the velocity an object falling only under the influence of gravity would have when it hit the ground?

Wednesday, Jan 6

On Wednesday's Physics class our main or big idea was proving horizontal motion and vertical motion are not related. We concluded that they were not related. We used a cannon on a car to show that when a ball is launched into the air vertically while the car was in motion at a constant velocity horizontally that it will still land in the same place because the ball will still keep its path horizontally after being launched into the air vertically.

the physics of snow

Since it's on all our minds....

Why does snow make everything seem much quieter?

Can it get too cool to snow?


Designer snowflakes from the lab

Physics of snowbaording (don't expect to do much of this tomorrow).

Study Hacks talks about deliberate practice

Another awesome blog post on why just working at something doesn't always make you better. You have to practice in a deliberate way.

What a study of chess experts teaches us about building a remarkable life

Some highlights:

What is deliberate practice?

It’s designed to improve performance. “The essence of deliberate practice is continually stretching an individual just beyond his or her current abilities. That may sound obvious, but most of us don’t do it in the activities we think of as practice.”

It’s repeated a lot. “High repetition is the most important difference between deliberate practice of a task and performing the task for real, when it counts.”

Feedback on results is continuously available. “You may think that your rehearsal of a job interview was flawless, but your opinion isn’t what counts.”

It’s highly demanding mentally. “Deliberate practice is above all an effort of focus and concentration. That is what makes it ‘deliberate,’ as distinct from the mindless playing of scales or hitting of tennis balls that most people engage in.”

It’s hard. “Doing things we know how to do well is enjoyable, and that’s exactly the opposite of what deliberate practice demands.”

It requires (good) goals. “The best performers set goals that are not about the outcome but rather about the process of reaching the outcome.”

Now here's the kicker—since deliberate practice is so hard,

Unless you’re a professional athlete or musician, your peers are likely spending zero hours on DP. Instead, they’re putting in their time, trying to accomplish the tasks handed to them in a competent and efficient fashion. Perhaps if they’re ambitious, they’ll try to come in earlier and leave later in a bid to outwork their peers.

But as with the intermediate-level chess players, this elbow-grease method can only get you so far.

That's right—most students, athletes, aren't doing anything close to deliberate practice.

What do you think will happen when you start doing deliberate practice?

Megawoosh

http://www.youtube.com/watch?v=lkwh4ZaxHIA

This was a 35.2 meter jump. There was tons of planning and physics that went into one jump. It was originally an ad for a Microsoft program called Microsoft office. The rest is on www.megawoosh.com 

The science of Avatar

Here are a few posts that describe the physics of the movie Avatar. In your lifetime, scientists have already discovered hundreds of extrasolar planets orbiting stars throughout the Milky Way (the first extrasolar planet was discovered in 1992).

The science of Avatar

Pandora could be a reality

More science of Avatar

Curious about how we discover extrasolar planets? Here's how.

You can even play a game to discover them on your own.

How to study distraction free

More last minute advice:

How to study distraction free

Mr. Burk's Top 5 Places to Study in Atlanta

One more great suggestion from Study Hacks is how Adventure Studying is a great way to prepare to study.

What is adventure studying? It's finding a cool, beautiful and quiet place for you to go away and study (and adventure doesn't involve Starbucks).

Here are my top 5 suggestions in the Atlanta Area:

1. The High Museum of Art—admission is a bit pricy ($15), but the cafe across the courtyard is free, rarely crowded and a great place to sit and admire the physics of the alexander calder mobile in the front (ever wonder how it stays balanced?)

2. Chuck E Cheese. You know you loved it 5 years ago. Why not go there, work for 45 minutes and then play some skee ball to put your physics knowledge to the test? If you go, bring headphones and find a quiet corner away from all the dancing robots.

3. A local college—Agnes Scott, Morehouse, Spelman, Emory, Georgia Tech—all of these places have beautiful campuses and libraries. It can be great fun to go to a college library for the afternoon.

4. The Carter Center--Recently completely renovated, you can visit a full scale model of the Oval Office (and that's a place where you really need to understand physics--check out Physics for Future Preisdents--a real course at UC Berkeley).

5. Outside—yes, it's supposed to be a bit rainy and cold this weekend, but it it would be great bundle up, to throw some FARMIPS and and some blank paper in your backpack, and go hike to some quiet, isolated place and solve physics problems under a tree.

movies you will need to analyze for class

Ball drop and toss

how to create an online calendar for the upcoming week

I've created a google spreadsheet to help you plan out your success week to help you demonstrate your best understanding on the exam. To use it, go here

Study Plan for Finals Week

The spreadsheet is read-only, so you'll need to make a copy.

To do that, click on "File > Make a copy" as shown in the image below.

If you'd like me to see your study plan, simply share it with me via google docs (this is completely optional).

5 Mistakes to avoid during finals

Here is more great advice from study hacks:

5 mistakes to avoid during finals.

We'll talk about this a bit tomorrow, but here they are briefly

• Mistake #1: Not Having a Clear Schedule
  
  You should set up a plan for using the time you have to maximum benefit—giving yourself time to rest, and reflect so you achieve maximum understanding.
  
  
• Mistake #2: Not Purging Your Obligations
  
  Avoid letting the little things in your life keep you from having the
  time you need to seriously prepare for exams.
  
  
• Mistake #3: “Studying”
  
  Focus on specific action. Solve problems.
  
  
• Mistake #4: Social Working
  
  While it can be helpful to work with others, often, working in a noisy space with friends can be very unproductive.
  
  
• Mistake #5: Calculating Your Final Grade
  
  I'll let Cal speak for himself:
  
  

  
  Don’t do this! No good can possibly come from such a superficial focus on the numbers. It will add stress. This, in turn, will make it harder for you to execute a reasonable, specific, and efficient study plan. Also, it’s just plain crass. You don’t want to be that person…
  

  
  

LHC is on!

THe LHC produced the first collisions of protons today.

Gamma Ray Satellite may have found dark matter

Here's another great post that describes a recent discovery of what may be dark matter, which makes up 20% of our universe (regular matter is only 4%).

The excess gamma rays could possibly be coming from a hypothesized dark matter called Weakly Interacting Massive Particles (WIMPs), colliding with one another and annihilating themselves into pure energy.

Fermi may have spotted dark matter.

Want to conquer stress? Exercise is key

Here's a great article from the NYT about a new study on rats showing that exercise allows our brains to better handle stress.

Here's a quote:

It looks more and more like the positive stress of exercise prepares cells and structures and pathways within the brain so that they’re more equipped to handle stress in other forms,” says Michael Hopkins, a graduate student affiliated with the Neurobiology of Learning and Memory Laboratory at Dartmouth, who has been studying how exercise differently affects thinking and emotion. “It’s pretty amazing, really, that you can get this translation from the realm of purely physical stresses to the realm of psychological stressors.

Posterous: another super cool tool!

Have you ever wanted to share a file, mp3, photo, or video without having to email everyone, or post an elaborate facebook status? Perhaps you have some great notes you want to share on the blog.

Well, here's the solution.

Just send an email to post@posterous.com, and attach whatever it is you want to share. Posterous will send you a link to the website you created with that attachment.

It couldn't be easier.