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Yesterday (June 8th) was my 15 min of fame at IHS for which I demonstarted a model rocket launch for my English class. The class was extremely excited and thought that the idea was great and took a lot away from the experience. The main theme for this launch, however, was wind. The wind was blowing from the SW at about 10 mph, which wreaks havoc for a small model rocket on a short field widthwise. As a result, I launched on the very southern edge of the field and when the parachute deployed, it caught the wind and brought the rocket to almost the same exact spot from where it was launched. The moral of this story? Weather plays a HUGE role in any sort of lfight, and it's extremely important to note varying conditions in order to have a successful launch, whether its a NASA shuttle or a small 14" tall rocket. Below, I've included a photo of the full launch setup. Also below is a brief countdown/ignition sequence from space shuttle Discovery's last and final mission that I shared with the class that day, and that I'm sure others will find it just as interesting.

Ignition sequence, and countdown (very brief and general. The real countdown is so long it usually takes days to complete once the shuttle is on the launch pad):

1.

2. T minus 31 s - the on-board computers take over the launch sequence.

3. T minus 6.6 s - the shuttle's main engines ignite one at a time (0.12 s apart). The engines build up to more than 90 percent of their maximum thrust.

4. T minus 3 s - shuttle main engines are in lift-off position.

5. T minus 0 s -the SRBs are ignited and the shuttle lifts off the pad.

6. T plus 20 s - the shuttle rolls right (180 degree roll, 78 degree pitch).

7. T plus 60 s - shuttle engines are at maximum throttle.

8. T plus 2 min - SRBs separate from the orbiter and fuel tank at an altitude of 28 miles (45 km). Main engines continue firing.

o Parachutes deploy from the SRBs.

o SRBs will land in the ocean about 140 miles (225 km) off the coast of Florida.

o Ships will recover the SRBs and tow them back to Cape Canaveral for processing and re-use.

9. T plus 7.7 min - main engines throttled down to keep acceleration below 3g's so that the shuttle does not break apart.

10. T plus 8.5 min - main engines shut down.

11. T plus 9 min - ET separates from the orbiter. The ET will burn up upon re-entry.

12. T plus 10.5 min - OMS engines fire to place you in a low orbit.

13. T plus 45 min - OMS engines fire again to place you in a higher, circular orbit (about 250 miles/400 km).

I recently travled down to Iroquois middle school to take advantage of a non-windy day to launch my favorite model rocket, and explore some physics in the process. The winds were coming from the South at about 7 mph, so the East end of the field had to be utilized for the launch, and everything went flawlessly because of planning ahead in this fashion.

Some specs of the solid fuel engine I used are as follows:

The average impulse is 5N/sec

Maximum thrust was 12.1N

Time to rise was about 3 seconds including delay between when the engine stopped until parachute deployment

Maximum altutude was about 400 feet

With all these stats, I concluded that the initial velocity off the pad was approximately 80m/s!!!!! Good thing these model rockets are unmanned...

Below is a picture of pre-launch setup

Physicists at Fermilab might have discovered a new particle that could be the most influential discovery of the past 50 years. Here's a link to the article from the New York Times....

http://www.nytimes.com/2011/04/06/science/06particle.html?_r=4&hp

I posted a thread on the homework forum, but no one has responded, so I'm hoping someone can help here. I need help for questions 2 and 8 and the most recent Phsycis-C Web Assign!!! For question 8, how do you find parts 4 and 5?

Here's a complex physics problem for you, with a real world application. About a year ago, my mom was in a car accident that prevents her still from playing the harp as her profession. In order to return to work, however, her physical therapist needs to know how much force it takes to pull a harp string (sufficient enough force to produce sound) so that he can tell if she is ready to exert that amount of force regularly. One might think that this would be a fairly simple SHM problem, but it's not quite that easy. Here are the conditions:

Each string is a different length, and thus each would require a different amount of force to pull.

There are three different types of strings, and each type is made up of a different material

The harder each string is pulled, the louder the sound, so the force would have to be calculated back from the amount of sound produced, and then pumped through SHM (I think...)

To give you an idea, the combined tension of the all strings on the soundboard is approximately 2.5 TONS. We're dealing with some large forces here. What would you do to solve this problem, and what information would you need? A very real world application of everything we've learned. The challenge is out there. Now the task is solving it.

In inspiration of our "shocking" in class demonstrations today, I felt the need for a random Google search. Can you Tesla coil???

The following image shows the Tesla coil at the Mid-America Science Museum in Hot Springs. It produces about 1,500,000 volts of electricity and is deemed the most powerful on earth. Anybody want to do the light bulb experiment with this?

Since the unintentional theme of my posts so far have revolved around Star Trek, I have decided to just go looking for stuff from the episodes that poses some amount of plausibility in our future. Today's topic: Invisibility Cloak

Apparently the technology isn't far off. Scientists have developed a material on a microscopic scale that they believe renders things "invisible" through it's ability to bend light. The process is called reverse refraction. You know how when you have a straw in a glass of water, the part below the water appears bent at a different angle then the part above the water? same concept. The material literally bends light around 3D objects without absorbing the light rays themselves, making items seem invisible. Maybe this Romulan and Klingon technology wasn't so far fetched after all.

To read more, here's the address: http://news.bbc.co.uk/2/hi/7553061.stm

I have just recently missed a full week of Physics lectures, among other things, and thought that I would drown in a sea of confusion when I got home, but alas no!! The online daily updates and postings of class lectures have proven themselves invaluable to helping em stay on track. So you may ask, why did I bother posting this? I have three reasons:

1) They actually work!! For anybody that misses class I highly suggest referring to the blog and daily updates. They also come in extreme handy when attempting homework and web-assigns.

2) To anyone outside of our school that's reading this post, I recommend that you do something similar for your students. I'm sure that you'll find that they understand the material better, and find it easier to stay on track, especially after missing class.

3) Many of the posts are just outright fun to read. The class notes are fun, but the real awesomeness comes from fellow students. Keep the entries coming!!

If you actually took the time to read all that, you deserve a special reward. Just a positive rant that I felt like going on with how useful this site has been

While I'm on a kick here (hard to guess what I find interesting right?), here's something I found on a totally different blog site about the possibilities of traveling faster than the speed of light. There is a very convincing theory, too bad no one knows where to get the energy....

And yes FizziksGuy, it uses "string guess". I'm very sorry.

Here's the link:

http://news.discovery.com/space/warp-drive-spaceship-engine.html

Here's something that I found online that looked pretty interesting. I'm a star wars junky (as well as star trek if you couldn't tell by my avatar...) and this technology is used pretty consistently in the movies. Hard to believe that it could be reality. In fact, ion engines are already in use today, but not over a wide-spread basis. Pretty awesome way to get some propulsion...

Just check out the attached URL to learn more and see some video clips

Trivia Fact: The "bad guys" in star wars fly what are called TIE fighters. Anyone care to guess what TIE stands for? It stands for Twin Ion Engines!!

http://www.newscientist.com/article/dn17476-ion-engine-could-one-day-power-39day-trips-to-mars.html

This is an online video of an MIT momentum lecture that I found, and that I found to be quite useful for what we learned in class. The lecture focuses on everything that we talked about in AP-C, but it was very interesting to hear the lesson from another professor's perspective. In this video are the definition of momentum, how it relates to force, as well as conservation of momentum and kinetic energy. One thing that I found particularly useful in the video were the derivations that the professor used, which helped me understand much better the relationships between multiple concepts such as force and momentum, force and impulse, etc. The video is almost an hour, so watching the whole thing in one sitting isn't highly recommend, but its great to skim through and revisit all the topics we covered and gain a little bit better understanding on some confusing ideas.

http://ocw.mit.edu/courses/physics/8-01-physics-i-classical-mechanics-fall-1999/video-lectures/lecture-15/