Friday, February 8, 2008
National Astronomy Week
February 18 - 24 is the celebration of National Astronomy Week, which is held every 3rd week of February. The theme of the celebration is: Enhancing the awareness of the public on the International Year of Astronomy 2009 (IYA2009). PAGASA will be conducting the following activities: astronomy lecture, stargazing and telescoping sessions, film showing and planetarium show. Astronomy related organizations are invited to do activities in their areas and promote an advocacy on astronomy.
Friday, February 1, 2008
Have FUN with physics
1. Most roller coasters are designed with elliptical loops in order to limit the centripetal accelerations experienced by the passengers. The elliptical loops are positioned with the major axis is perpendicular to the Earth. This ellipse has a major axis AM, a minor axis am, an eccentricity of å and the ride is designed to give riders a feeling of weightlessness at the top of the loop. Find the following, expressing all answers in terms of the eccentricity and the major axis.
a) Minimum velocity needed at the top of the loop. so far: Fnormal +mg = (mass x velocity top squared)/radius
b) The radial normal force at the minor axis under the condition of a)
c) Net normal force experienced by the passengers at the minor axis asthey move towards the top of the loop. Discuss the results aseccentricity approaches zero and one.
2. A pirate ship is moving along the coastline, trying to overtake a merchantship making for a harbor. At the rear of the merchant ship flies a flag. You are sure that the ship can be convinced to surrender if you can blow the flagoff with a single shot! You’ll have to set the fuse to the proper length so the cannonball explodes just as it reaches the flagpole. The cannon mounted on the front of your ship has a maximum horizontal range of 950 meters (at 45degrees), so you’ll use it to make the shot.Consider the following in making your calculations: The straight -line distancefrom your cannon to the flag is 650 meters due East. Your ship has a speed of3 knots with respect to the water surface at a heading of 45 degrees south of east. The merchant ship has a speed of 4 knots with respect to the watersurface and is heading northeast. The fuse in the cannonball burns at a rate of2 cm/second. The flag is mounted at the same height as the cannon. Hint:transform to a coordinate frame attached to the cannon
a) You’ll want to keep the trajectory low, so the other ship can’t take evasive action after your shot. If your angle of elevation is to be a maximum of 30 degrees with respect to the water surface, what length of fuse is needed?
b) How long after sighting the ship will you take your shot?
c) With respect to the direction of travel of your pirate ship, at what angle should you aim the cannon when you fire the shot?
You may need physical constant not provided in these problems. Look them up. Show all calculations.Express answers in scientific notation with 3 significant digits of accuracy.
3. In a region of space near a group of charged particles, the potential energy function can be written as a function of distance from the center of the group. In particular, the potential energy may be written asU(x)= x4/5 – 15x3 + 125x2 +100which has units of electron-volts when x is in centimeters.Knowing that the forces exerted by charged particles are conservative, answerthe following questions about an electron in the region within 20 cm of the center of the group
a) At which locations within this range will the forces acting on theelectron be in equilibrium?
b) Which of these are stable equilibrium locations?
c) What is the maximum velocity (m/s)that an electron can have if it is toremain ‘trapped’ within the region?
d) What fraction of the speed of light is this?
a) Minimum velocity needed at the top of the loop. so far: Fnormal +mg = (mass x velocity top squared)/radius
b) The radial normal force at the minor axis under the condition of a)
c) Net normal force experienced by the passengers at the minor axis asthey move towards the top of the loop. Discuss the results aseccentricity approaches zero and one.
2. A pirate ship is moving along the coastline, trying to overtake a merchantship making for a harbor. At the rear of the merchant ship flies a flag. You are sure that the ship can be convinced to surrender if you can blow the flagoff with a single shot! You’ll have to set the fuse to the proper length so the cannonball explodes just as it reaches the flagpole. The cannon mounted on the front of your ship has a maximum horizontal range of 950 meters (at 45degrees), so you’ll use it to make the shot.Consider the following in making your calculations: The straight -line distancefrom your cannon to the flag is 650 meters due East. Your ship has a speed of3 knots with respect to the water surface at a heading of 45 degrees south of east. The merchant ship has a speed of 4 knots with respect to the watersurface and is heading northeast. The fuse in the cannonball burns at a rate of2 cm/second. The flag is mounted at the same height as the cannon. Hint:transform to a coordinate frame attached to the cannon
a) You’ll want to keep the trajectory low, so the other ship can’t take evasive action after your shot. If your angle of elevation is to be a maximum of 30 degrees with respect to the water surface, what length of fuse is needed?
b) How long after sighting the ship will you take your shot?
c) With respect to the direction of travel of your pirate ship, at what angle should you aim the cannon when you fire the shot?
You may need physical constant not provided in these problems. Look them up. Show all calculations.Express answers in scientific notation with 3 significant digits of accuracy.
3. In a region of space near a group of charged particles, the potential energy function can be written as a function of distance from the center of the group. In particular, the potential energy may be written asU(x)= x4/5 – 15x3 + 125x2 +100which has units of electron-volts when x is in centimeters.Knowing that the forces exerted by charged particles are conservative, answerthe following questions about an electron in the region within 20 cm of the center of the group
a) At which locations within this range will the forces acting on theelectron be in equilibrium?
b) Which of these are stable equilibrium locations?
c) What is the maximum velocity (m/s)that an electron can have if it is toremain ‘trapped’ within the region?
d) What fraction of the speed of light is this?
Ubuntu on my AMD64
I managed to install Ubuntu into my HP Pavilion DV6604nr (AMD 64-Bit AthlonX2) last night. But I'm still trying to figure out how to dual boot between Ubuntu and my new Windows XP OS. Pics below.
Friday, January 18, 2008
International Year of Astronomy 2009
This coming 2009, the world is going to celebrate the International Year of Astronomy (IYA). The International Astronomical Union (IAU) declared 2009 as the year of astronomy since it corresponds to the 400th anniversary of Galileo's observation of the night sky. The Philippines being a signatory of the IAU will participate in this global event. The physics department of Silliman is being invited by Ms. Cynthia Celebre, chief of the AsRDS of PAGASA, to participate in the activities of the IYA.
The events for the IYA are currently being planned out by the IAU. The activities in the Philippines would include traveling exhibits, a quiz show, a series of lectures, telescope and binocular using, and the organization of the first National Astronomy Congress.
The events for the IYA are currently being planned out by the IAU. The activities in the Philippines would include traveling exhibits, a quiz show, a series of lectures, telescope and binocular using, and the organization of the first National Astronomy Congress.
Monday, January 7, 2008
Ask the Physicists
Ask us! Just "comment" it below. (reposted)
Order of appearance:
Bryan King - Computers & gadgets
Marvin Flores - Quantum & more
Ronmel Ross - Sports
Norman Marigza - Astronomy
Francis Quiogue - War & food
Don't worrry. There are more of us.
Order of appearance:
Bryan King - Computers & gadgets
Marvin Flores - Quantum & more
Ronmel Ross - Sports
Norman Marigza - Astronomy
Francis Quiogue - War & food
Don't worrry. There are more of us.
Thursday, January 3, 2008
Wednesday, January 2, 2008
2008 What Day is Today? Really.
2008 What Day is Today? Really.*
by Bryan Vincent King
*intended for entertainment purposes only
January 1 - Avoid Getting Blown Up Day
January 2 - Clean Your House Safely Day
January 3 - Slouch At Work Day
January 4 - Check Potato Prices Day
January 5 - Brain Explosion Day
January 6 - Tug Your Brother's Shirt Day
January 7 - Mascot Day
January 8 - Drink Through A Straw Day
January 9 - Ride A Motorcycle While Wearing An Orange Shirt Day
January 10 - Bake A Cake Day
January 11 - Buy A Really Old CD Day
January 12 - Become A Creepy Idiot Day
January 13 - Visit Your Imaginary Island Day
January 14 - Prevent A Zit Day
January 15 - Listen To Classic Music Day
January 16 - Forget You Were A Pirate Day
January 17 - Stand On Your Car And Shout "Freedom!" Day
January 18 - Smell Your Fridge Day
January 19 - Visit A Mall And Buy Nothing Day
January 20 - Wake Up Very Early Day
January 21 - Talk Like A Drunkard Day
January 22 - Skin A Potato Day
January 23 - Soak Your Clean Clothes Day
January 24 - Get Drunk With Water Day
January 25 - Wear Huge Boots and Think You're A Cowboy Day
January 26 - Speak In An Invented Language Day
January 27 - Believe Diamonds Are Cheap Day
January 28 - Attempt A Double Jump Day
January 29 - Sleep At Another Person's Bed Day
January 30 - Audition For Something You're Not Good At Day
January 31 - Discover Art Day
Will update for the remaining months.
by Bryan Vincent King
*intended for entertainment purposes only
January 1 - Avoid Getting Blown Up Day
January 2 - Clean Your House Safely Day
January 3 - Slouch At Work Day
January 4 - Check Potato Prices Day
January 5 - Brain Explosion Day
January 6 - Tug Your Brother's Shirt Day
January 7 - Mascot Day
January 8 - Drink Through A Straw Day
January 9 - Ride A Motorcycle While Wearing An Orange Shirt Day
January 10 - Bake A Cake Day
January 11 - Buy A Really Old CD Day
January 12 - Become A Creepy Idiot Day
January 13 - Visit Your Imaginary Island Day
January 14 - Prevent A Zit Day
January 15 - Listen To Classic Music Day
January 16 - Forget You Were A Pirate Day
January 17 - Stand On Your Car And Shout "Freedom!" Day
January 18 - Smell Your Fridge Day
January 19 - Visit A Mall And Buy Nothing Day
January 20 - Wake Up Very Early Day
January 21 - Talk Like A Drunkard Day
January 22 - Skin A Potato Day
January 23 - Soak Your Clean Clothes Day
January 24 - Get Drunk With Water Day
January 25 - Wear Huge Boots and Think You're A Cowboy Day
January 26 - Speak In An Invented Language Day
January 27 - Believe Diamonds Are Cheap Day
January 28 - Attempt A Double Jump Day
January 29 - Sleep At Another Person's Bed Day
January 30 - Audition For Something You're Not Good At Day
January 31 - Discover Art Day
Will update for the remaining months.
Tuesday, January 1, 2008
Make your 8 new year resolutions for 2008!
2008 has finally arrived. I don't really make new year resolutions but this year, I'll try to make them realistic for myself. Here are my eight new year resolutions for 2008:
1.) Be healthy. I'm slim and I don't plan on losing weight. Instead, I might hit the gym to buff up and eat right, which means less junk food, less soda, and more fruits & veggies.
2.) Play more sports. All work and no play is boring. I have forgotten the joy of basketball, track & field, and soccer, and I think it's time I came back.
3.) Do more. Sleep less. Even with school, it's not enough to keep me off my bed. When I sleep, I need at least 10 hours of it but I know I can do with less.
4.) Think more of myself. Some people have hinted I do too much for friends while some say I do little for them compared to other people in the same group. It's time I thought of myself more and make it clear to them there's always this level of friendship that makes barriers.
5.) Learn more. Lectures, books, and more educational opportunities await. Time for me to grab them.
6.) Volunteer. Nothing feels better than doing something for the community. I should be able to find at least ONE place to volunteer in.
7.) Do two daring tasks. Whether it be singing or dancing in a show where I have no ability to do so, I'm going to do it! (no illegal/immoral stuff)
8.) At least 80% completion of my thesis. Besides staying with the Physics program, I have to do well on my thesis and finish it before time runs out.
Share to us your eight New Year Resolutions!
Just comment below.
1.) Be healthy. I'm slim and I don't plan on losing weight. Instead, I might hit the gym to buff up and eat right, which means less junk food, less soda, and more fruits & veggies.
2.) Play more sports. All work and no play is boring. I have forgotten the joy of basketball, track & field, and soccer, and I think it's time I came back.
3.) Do more. Sleep less. Even with school, it's not enough to keep me off my bed. When I sleep, I need at least 10 hours of it but I know I can do with less.
4.) Think more of myself. Some people have hinted I do too much for friends while some say I do little for them compared to other people in the same group. It's time I thought of myself more and make it clear to them there's always this level of friendship that makes barriers.
5.) Learn more. Lectures, books, and more educational opportunities await. Time for me to grab them.
6.) Volunteer. Nothing feels better than doing something for the community. I should be able to find at least ONE place to volunteer in.
7.) Do two daring tasks. Whether it be singing or dancing in a show where I have no ability to do so, I'm going to do it! (no illegal/immoral stuff)
8.) At least 80% completion of my thesis. Besides staying with the Physics program, I have to do well on my thesis and finish it before time runs out.
Share to us your eight New Year Resolutions!
Just comment below.
Friday, December 28, 2007
Decline of SU?
I agree that some units in SU are not doing as well as their counterparts in other universities, or as well as they were in the past, but there are a number who are.
Consider this... "Silliman now has the most Level III offerings than any school in the country" (http://www.su.edu.ph/pres_speaks/bsm_strategicchallenges_silliman.htm).
SU also has 4 Centers of Excellence: Nursing, Education, Marine Science, and Accountancy;
and 2 Centers of Development: Biology and Information Technology.
Some of them got their upgraded status only quite recently, so there must be improvements going on around SU. So, keep your head up, because the way things are going, we're on a steady rise.
Consider this... "Silliman now has the most Level III offerings than any school in the country" (http://www.su.edu.ph/pres_speaks/bsm_strategicchallenges_silliman.htm).
SU also has 4 Centers of Excellence: Nursing, Education, Marine Science, and Accountancy;
and 2 Centers of Development: Biology and Information Technology.
Some of them got their upgraded status only quite recently, so there must be improvements going on around SU. So, keep your head up, because the way things are going, we're on a steady rise.
Sunday, December 23, 2007
Assignment on BioPhysics
1.) The equation of a certain traveling transverse wave is given below:
y = 2 sin 2 pi [ (t/0.01) - (x/30) ]
where x and y are in cm, and t in seconds.
What are the waves:
a) amplitude
b) wavelength
c) frequency
d) speed of propagation
2.) What is the difference between the speeds of longitudinal waves in air at -3 degrees Celsius and 57 degrees Celsius?
Merry Christmas guys!
y = 2 sin 2 pi [ (t/0.01) - (x/30) ]
where x and y are in cm, and t in seconds.
What are the waves:
a) amplitude
b) wavelength
c) frequency
d) speed of propagation
2.) What is the difference between the speeds of longitudinal waves in air at -3 degrees Celsius and 57 degrees Celsius?
Merry Christmas guys!
Friday, December 21, 2007
Thursday, December 20, 2007
TTMS Worm: Removal & Prevention
My friend's flash drive has been infected with a worm that disables the user to open it directly by simply double-clicking and even through "exploring" it by right-clicking then selecting Explore. Sometimes, it displays this line: "TTMS NAA NA DIRI, DON’T WORRY I’M NOT A CORRUPT LIKE YOU!" especially when you try going into the registry.
This, along with other .vbs or .wsh viruses/worms/trojans, can easily be removed and prevented by doing any of the following methods:
Screenshot taken from www.linux.org
Some of you might be wondering what LINUX is. It is an open source operating system which you can get for free. Most viruses are targeted only at Microsoft's operating systems like Windows 98, XP, ME, 2000, and Vista. Since this worm has an extension (.vbs), then it only targets Windows (which is capable of running visual basic scripts).
First, find someone who has Linux installed on their laptop or desktop and boot into that system. If you have your own Linux OS, that's great! It doesn't have to be a specific flavor of Linux. It can be Fedora, Ubuntu, or PCLinuxOS. As soon as you have booted into the system, plug in your drive and open it. Find the files which ends with .vbs or something like TTMS1218.dll.vbs. That is the problem.
E.) Format your computer
This is the last resort to removing any other kind of viruses. This worm, TTMS, isn't that hard to remove especially if you use a Linux machine to remove it, but never do this method before backing up all your data first.
=======================================================================
TTMS has several definitions and the nearest one I found was "Trojan Transportable Mini-Switch" found here. This worm could have been written by someone outside the Philippines and was edited by a Filipino by simply changing the output error message into Cebuano.
When I plugged the infected device into PCLinuxOS, I managed to get the source code by opening the .vbs file in KWrite. Here's a screen shot:
Image taken on Dec. 20, 2007
=========================================================
I do not own AVAST, AVG, BitDefender, and Analog X & its software.
All images here were taken on Dec. 20, 2007.
This, along with other .vbs or .wsh viruses/worms/trojans, can easily be removed and prevented by doing any of the following methods:
CAUTION: None of these methods are fully 100% safe. Even using an updated anti-virus may cause irreversible damage to your Windows computer. BACK UP YOUR DATA FIRST! I am in no way responsible for any lost data, corrupted files, or any of the like. You have the sole responsibility to your computer. Proceed at your own risk!
A.) Use your anti-virus
Screen shot taken from http://www.avast.com/
This is the most easiest way to remove the worm. However, if your definitions are not updated, then they may not be detected and thus you cannot remove them. There are only a few free anti-virus software like AVG, Avast, and BitDefender. I suggest using a primary one, either AVG or Avast and as a back-up, BitDefender. AVG/Avast will most likely find the worm you have and BitDefender is a good back-up anti-virus since it lacks the real-time scanner (Real time scanner means that while your browsing a folder, and your anti-virus manages to see a virus, it warns you in "real time" without scanning the whole folder or drive manually. AVG and Avast have this real time scanner while BitDefender does not.)
B.) Disable .vbs scripts on your Windows machine manually
Most viruses are written in Microsoft's Visual Basic. It's a simple programming language with a graphical user interface (GUI) and allows the user to easily create programs that they need. However, viruses, worms, and trojans, are also created in this manner.
Although I do not recommend this process for the programmers, basic users can disable the running of .vbs files and other dangerous formats through disabling the Windows Scripting Host. Click here to view the link. Find your operating system, and follow the guide. Use the Windows 2000 guide if you are using XP/Vista. Again, this step is not recommended for programmers who use Visual Basic or do programming. Proceed at your own risk.
C.) Download and install Script Defender by Analog X
Image screen shot taken from http://www.analogx.com/contents/download/system/sdefend.htm
If you are afraid of doing letter B, then you can use this software to manage your file extensions instead. This simply allows you to monitor certain types of file extensions like .vbs and .wsh. When they try to execute themselves, Script Defender will not allow them to do so unless you allow it. It basically asks you first before the file executes. Think of it this way, the virus shows up and decides to steal all your personal information in your entire system. It can and it will, but Script Defender makes the virus ask you first before it does so. Pretty neat, eh? Download it here. Please read below before using.
D.) Plug the USB flash drive into a Linux computer.
Screen shot taken from http://www.avast.com/
This is the most easiest way to remove the worm. However, if your definitions are not updated, then they may not be detected and thus you cannot remove them. There are only a few free anti-virus software like AVG, Avast, and BitDefender. I suggest using a primary one, either AVG or Avast and as a back-up, BitDefender. AVG/Avast will most likely find the worm you have and BitDefender is a good back-up anti-virus since it lacks the real-time scanner (Real time scanner means that while your browsing a folder, and your anti-virus manages to see a virus, it warns you in "real time" without scanning the whole folder or drive manually. AVG and Avast have this real time scanner while BitDefender does not.)
B.) Disable .vbs scripts on your Windows machine manually
Most viruses are written in Microsoft's Visual Basic. It's a simple programming language with a graphical user interface (GUI) and allows the user to easily create programs that they need. However, viruses, worms, and trojans, are also created in this manner.
Although I do not recommend this process for the programmers, basic users can disable the running of .vbs files and other dangerous formats through disabling the Windows Scripting Host. Click here to view the link. Find your operating system, and follow the guide. Use the Windows 2000 guide if you are using XP/Vista. Again, this step is not recommended for programmers who use Visual Basic or do programming. Proceed at your own risk.
C.) Download and install Script Defender by Analog X
Image screen shot taken from http://www.analogx.com/contents/download/system/sdefend.htm
If you are afraid of doing letter B, then you can use this software to manage your file extensions instead. This simply allows you to monitor certain types of file extensions like .vbs and .wsh. When they try to execute themselves, Script Defender will not allow them to do so unless you allow it. It basically asks you first before the file executes. Think of it this way, the virus shows up and decides to steal all your personal information in your entire system. It can and it will, but Script Defender makes the virus ask you first before it does so. Pretty neat, eh? Download it here. Please read below before using.
After you have installed it, press "install intercepts" and it will intercept anything that was placed in the dialog box before it executes. However, do not add any file extensions you want to block which you might regret later. Use the default that it already has. I tried adding .txt to it, and it did work, but when I removed .txt and opened a .txt file, it gave me some sort of error saying that it couldn't open it. I could open it through notepad but not through double-clicking it. Again, proceed at your own risk and don't add anything you will regret later.
D.) Plug the USB flash drive into a Linux computer.
Screenshot taken from www.linux.org
Some of you might be wondering what LINUX is. It is an open source operating system which you can get for free. Most viruses are targeted only at Microsoft's operating systems like Windows 98, XP, ME, 2000, and Vista. Since this worm has an extension (.vbs), then it only targets Windows (which is capable of running visual basic scripts).
First, find someone who has Linux installed on their laptop or desktop and boot into that system. If you have your own Linux OS, that's great! It doesn't have to be a specific flavor of Linux. It can be Fedora, Ubuntu, or PCLinuxOS. As soon as you have booted into the system, plug in your drive and open it. Find the files which ends with .vbs or something like TTMS1218.dll.vbs. That is the problem.
After you have removed the files, safely unmount by right clicking the icon of your device and left clicking on remove or unmount. (NOTE: Some of the flavors might require you for administrative access or the use of the terminal to mount/unmount the drive.)By the way, while your USB is mounted on the Linux system, you might find other viruses, trojans, or worms. If you suspect that they are, please be careful in deleting them. They could be files you really need.
E.) Format your computer
This is the last resort to removing any other kind of viruses. This worm, TTMS, isn't that hard to remove especially if you use a Linux machine to remove it, but never do this method before backing up all your data first.
=======================================================================
TTMS has several definitions and the nearest one I found was "Trojan Transportable Mini-Switch" found here. This worm could have been written by someone outside the Philippines and was edited by a Filipino by simply changing the output error message into Cebuano.
When I plugged the infected device into PCLinuxOS, I managed to get the source code by opening the .vbs file in KWrite. Here's a screen shot:
Image taken on Dec. 20, 2007
=========================================================
I do not own AVAST, AVG, BitDefender, and Analog X & its software.
All images here were taken on Dec. 20, 2007.
Wednesday, December 19, 2007
Meteor Shower Viewing at Silliman
Last Friday, Dec. 14, the physics students of Silliman gathered to watch the Geminids meteor shower. Aside from the physics majors, other students joined in watching the said meteor shower.
Wednesday, December 12, 2007
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