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Wall of Pure Awesome
1945 Computer Game
micronesia, Oct 11 2008
Have any of you played 1945? It's a scrolling shooter where you control an American airplane and fight against Japanese fighters (I believe, at least). For a grad class, I have to make computer games, and this was one of the games we were instructed to make. With the help of a tutorial I went ahead and made it. You can download it at
After playing it for a little while I found a couple of minor bugs, however it seems to work pretty well. Watch out for the white planes... they are dangerous! But, they are worth the most points :D
What highest score did you get?
Do you have any cool little computer games to share? I'm going to be making more, so I'll probably share them also.
After a hiatus, the physics blog is back. Last time there was some disagreement and interesting discussion about if the author of the question I borrowed was in fact wrong. I'm honestly still not 100% sure, but I'll try to pick a question that is less likely to create disagreement that won't be resolved.
Last week the question of the week was:
Question 3 Momentum and Energy
An open railroad car is rolling without friction in a vertically-falling downpour and an appreciable amount of rain falls into the car and accumulates there. Consider the effect of accumulating rain on the speed, momentum, and kinetic energy of the car.
1) The speed of the car will (a) increase (b) decrease (c) not change
2) The momentum of the car will (a) increase (b) decrease (c) not change
3) And the kinetic energy of the car will (a) increase (b) decrease (c) not change
The rain has now stopped. A drain plug is opened in the bottom of the rolling car allowing the accumulated water to run out. Consider the effects of the draining water on the speed, momentum, and kinetic energy of the rolling car.
4) The speed of the car will (a) increase (b) decrease (c) remain the same
5) The momentum of the car will (a) increase (b) decrease (c) remain the same
6) And the kinetic energy will (a) increase (b) decrease (c) remain the same
Go ahead and look back to your post in the last thread here. Rethink your reasoning, then proceed to the answers. You need to make the assumption that he's referring to the speed/momentum/energy of the car including its contents, but that makes sense as the default assumption anyway.
I'd assign this a 2/5 difficulty rating because it's basic applications of simple physics principles, but it's still quite easy to slip up. betaben was close, but fight_or_flight won.
We'll settle any disagreements with a bo9 on lost temple. But seriously, if the answers don't make sense, please ask!
Question 4 Rotation
Please remember to post answers in SPOILERS, and preferably with an explanation.
I have to make a decision soon and I'm not sure which way to go, so I'm thinking I'll ask for some input and then make a decision. It's getting late and I'd rather decide before I go to bed, so I'll probably just take into account any posts that come soon after the OP is posted.
I found out this morning that my grandfather passed away in the middle of the night... one of those situations where they could have kept him alive using machinery, but decided to let him go. Recall my earlier blog where I pointed out that my grandmother passed away (other side of the family). This was in January, and the shock of finding out my grandfather died, in combination with being tired in the morning, prevented it from really sinking in. I've felt a bit strange today, but still I haven't had that feeling of grief and sadness that I had the day I found out my grandmother died.
Some other explanations could include that I haven't actually seen my grandfather in person in a few years (he lived in Florida) and he lived far away. However, I had spoken to him on the phone recently. I had a good relationship with him even though we only saw each other once every few years once I got older.
So the decision is this. I had off today (Thursday) for a school holiday, and I have off Monday for another holiday. Sunday is the funeral. I briefly e-mailed my boss who told me to take time off if I need to (in a family-first sorta way). The only day that would make sense to take off is tomorrow (Friday). Now, if I feel okay tomorrow like I did today, then I shouldn't have too much trouble going in to work. But, I'm nervous that it's going to hit me sooner or later and I'm going to be upset (edit: keep in mind I'm a teacher so it's sorta like being an actor who needs their head in the game to perform). But it makes things a little harder for me at work if I call in that I'm not coming in.
Should I put in for a sub and take the day, or try to go in tomorrow? The day my grandmother passed away I was pretty upset and wouldn't have gone into work that day, and I'm nervous tomorrow might become similar to that day. I just feel awkward assuming that I won't be okay like I was today. I'd make a poll but I really don't want people just silently voting... I'd rather hear some reasoning.
Feel free to not respond if you can't think of anything that you think will help. After all, this is a strange request where you probably lack the necessary information to draw any clear conclusions.
edit: Um I'm not talking about skipping the Sunday funeral for those who are confused... I'm talking about skipping Friday work.
I need a green striped polo like the one featured here:
The pants, and black belt I already have. I tried searching online for a shirt like that but I cannot find one for the life of me. Some of the near misses:
The criteria:
Dark Green stripes and Light Green stripes
Stripes should be same thickness
Stripes should be fairly thick like shown on Steve
If a can of compressed air is punctured and the escaping air blows to the right, the can will move to the left in a rocket-like fashion. Now consider a vacuum can that is punctured. The air blows in the left as it enters the can. After the vacuum is filled the can will:
a) be moving to the left b) be moving to the right c) not be moving
The correct answer is c. First of all, for those who were confused about which way the can was punctured, I agree the wording was a bit tricky... but it didn't matter!
It's very easy to get confused by this problem because there is going to be a momentarily slight oscillation about the center of mass. Just as the can is punctured, the pressure that was being exerted by the atmosphere on the now-absent piece of metal doesn't exist anymore... and the force acting on that surface is weaker than that acting on the opposite side of the can. However, the air rushing into the can will eventually hit the opposite wall, which will provide that force (plus a bit extra until everything equals out). These two drawings I made should clear it up:
I assign this problem a difficulty level of 3 out of 5 because it's easy to confuse the physics principles.
Congratulations to Xeofreestyler for being the first to provide the correct answer and provide a reasonable justification. Dr.Dragoon named the problem.
There were a lot of explanations that were either wrong (even among people who chose C) or not backed up. For example: saying 'C because conservation of momentum' isn't necessarily wrong, but is not sufficient in my opinion. There were a few explanations that I am not sure if they are correct or not... although nobody quite used the one that I provided. Feel free to provide further analysis.
Question 3 Momentum and Energy
An open railroad car is rolling without friction in a vertically-falling downpour and an appreciable amount of rain falls into the car and accumulates there. Consider the effect of accumulating rain on the speed, momentum, and kinetic energy of the car.
1) The speed of the car will (a) increase (b) decrease (c) not change
2) The momentum of the car will (a) increase (b) decrease (c) not change
3) And the kinetic energy of the car will (a) increase (b) decrease (c) not change
The rain has now stopped. A drain plug is opened in the bottom of the rolling car allowing the accumulated water to run out. Consider the effects of the draining water on the speed, momentum, and kinetic energy of the rolling car.
4) The speed of the car will (a) increase (b) decrease (c) remain the same
5) The momentum of the car will (a) increase (b) decrease (c) remain the same
6) And the kinetic energy will (a) increase (b) decrease (c) remain the same
Remember to spoiler your answers and explanations, at least on the first page!
Micronesia exercises his dog yubee on a 15-minute walk by throwing a stick that yubee chases and retrieves. To keep yubee running for the longest time as Micronesia walks, which way should he throw the stick?
a) In front of him b) In back of him c) Sideways d) In any direction, as all are equivalent
The correct answer is d. This is an example of a question that you have to read carefully, and not get tricked by your assumptions about what the question is expecting of you. The goal is to determine how you could keep yubee running for the longest time. The problem specifically says it is a 15 minute walk. It doesn't matter which way or how fast yubee runs. As long as the 15 minutes isn't up, the walking will continue. Once the 15 minutes is up, yubee is done running. I assign this problem a difficulty level of only 1 out of 5 because the physics is trivial. But it's somewhat tricky for reasons other than physics.
Congratulations to Hippopotamus for being the first person to provide the correct answer and adequately explain it (at least I think he did ooa). Makhno was the second person who seemed to give a nice explanation! :D
So the moral of the story: be sure you're answering the question that is asked!
Question 2 Newton's Laws of Motion
If a can of compressed air is punctured and the escaping air blows to the right, the can will move to the left in a rocket-like fashion. Now consider a vacuum can that is punctured. The air blows in the left as it enters the can. After the vacuum is filled the can will:
a) be moving to the left b) be moving to the right c) not be moving
Remember to post not only your answer, but your reasoning/explanation if you want to receive credit for being the winnAr.
As any seasoned tl blog reader would agree, physics is a topic seen most predominantly in 'help me with my hw' type threads. Physics is indeed a course that many people who lack the background or interest take due to a requirement for school/work. In fact, this effect has become so exaggerated that most people don't seem to realize just how interesting, relevant, and fundamental physics really can be (and is).
I'm not bringing this up due to some kind of attempt to be a responsible educator of physics. My motivation is more simple. I like physics, and I don't like to see it misrepresented until it drives many people to dislike it.
I have access to a nice collection of thought provoking physics questions of various levels. My plan is to post one question (multiple choice) minus the answer, and ask for people to provide in spoilers their prediction of what the answer is, and an explanation. I suppose I should pick the first response that adequately answered the question, and feature them as the previous week's winner.
I'm going to choose a question of varying difficulty from the following topics (probably will sequentially run through the topics):
Mechanics: Kinematics Newton's Laws of Motion Momentum and Energy Rotation Gravity
Fluids
Heat
Vibrations
Light
Electricity and Magnetism
Relativity
Quanta
The goal is for every reader to encounter at least one question that is difficult enough to challenge them while being within their knowledge/ability to answer correctly. These problems are mostly simple at face value, but at times can fool even graduate students in physics programs, so don't sell them short! Upon the conclusion of the question, I will provide my own estimate of the difficulty of the question on a scale of 1-5 with 1 being easiest.
Question 1 Kinematics
Micronesia exercises his dog yubee on a 15-minute walk by throwing a stick that yubee chases and retrieves. To keep yubee running for the longest time as Micronesia walks, which way should he throw the stick?
a) In front of him b) In back of him c) Sideways d) In any direction, as all are equivalent
On August 30th I noticed our clan leader had made a news post to go along with a new website. This leader has been providing a website and channel for close to a decade, so I'm hesitant to make any joke at his expense. However, seeing how he's a non-combatant and not much more than a figurehead, I'll allow the power of funny to prevail.
I was seriously cracking up as I read this. I'm sure not everyone will find it funny, and a few might not even get what I mean when I say it's funny, but it's funny.
Welcome to StarCraft Confederacy. It has been many years since this clan has been established. Our clan existance begins back in August of 1999. A fearless leader named SCC-Duke took on the roll of beginning StarCraft Confederacy. Who knew that Clan SCC will last for 9 years and is still alive presently? It is great devotion and hard work not only from me, but members over the years to make this clan a success.
No I'm not talking about by.Flash. Once again, I'm talking about a video made in flash animation. Only this time, it can't be placed in the same category.
This one was made by my sister of the past day or so. Just as I was learning Flash, she was also, although she's a better artist, a quicker learner with art software, and has more time than me
