Feb 09
Question from here and here (and probably lots of other places on the net by now!).
“A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?”
Rob sent this to me this morning. I said ‘No’ the plane wouldn’t take off. I understand completely the point that the thrust from a planes engine does not act through the wheels of the plane, and I used to fly so I’m fairly sure that I understand the principles of lift/drag etc.
The issue is that the question has been specifically worded to cause to differing opinions in two types of people.
The practical thinkers will assume that the plane is using it’s engines and that the thrust will simply push it forwards, regardless of the conveyor’s speed, as the frictional force between the conveyor and the wheels is negligible and the thrust from the engines acts upon the air and not the wheels. They will say the the plane does take off, and they’d be correct.
However, the theoretical thinkers will ignore the real-world practicalities of the situation because it would never exist. Instead they abstract it to a simple object with a given speed, which is being kept motionless by something exserting a force in the opposite direction. They correctly calculate that the net speed of the object will be nothing and therefore there would be no airflow over the wings of the plane to allow it to take off. They are also correct.
In reality, both answers are equally valid depending on your point of view and how you interpret the question, which has been worded very badly (on purpose, I’m sure).
This reminds me of a question once asked by my physics teacher. If popeye is sitting in a sailboat and blows on the sail, will the boat move?
Jan 04
Earlier today I searched the internet for a 2006 wall planner - kind of like the Sasco wall planners that you see on office walls. I didn’t find what I was looking for, apart from a couple of sites wanting to sell me the real thing and a couple of dodgy looking JPGs, so I spent some time during my lunch hour creating one. It’s done in Microsoft Excel format and there are both horizontal and vertical versions. Feel free to download them using the following links.
2006 Horizontal Planner
2006 Vertical Planner
The holidays are official UK holidays taken from the DTI’s web site.
If you find these planners useful, please consider making a small donation
I’m not entirely sure about the colours or layout, so if you have any suggestions, please leave a comment and I will see what I can do.
Update: 19/10/2006 - Due to popular demand, I have created a set for 2007 as well
Jan 03
I was a very lucky boy this year… I must have been on Santa’s ‘nice’ list for sure! I got:
- A PlayStation Portable (a Value pack & “Coded Arms” game)
- A big wad of cash, which I used to buy PSP stuff (512Mb Memory stick, Burnout: Legends, Archer Mclean’s Mercury, Prince of Persia: Revelations and Lumines)
- An excellent pocket tripod for my camera - Much better than the cheap Hama tripod I had. It’s a Kaiser pocket tripod 5005, which can be used as a clamp-on or table-top tripod. I’ll post a review and pictures another time.
- Some really nice clothes
- New boots
- A couple of nice books
- Lots of smelly stuff (shower gel, soap, deodorant) - Do you think people are trying to tell me something?!?
- Lots of chocolate!
- Lot’s of other smaller bits and pieces which are too numerous to list!
Jan 03
Today’s my first day back at work after Christmas. I have to say it’s a pretty slow day, but I guess that’s to be expected.
I’m proud to announce that I managed my new-years resolution of getting up and getting to work earlier today. I hope I manage to keep it up!
Dec 25
Meeeerrrrrrry Christmas, and a happy new year!
Dec 19
As just reported by The register, a recent Microsoft update causes problems with Internet Explorer 6 if you’ve previously run version 7 (beta) in ’standalone’ mode.
This hit me, but I was blaming it on a recent install of the Opera web browser as that and the update coincided, so apologies to Opera. The problem I was experiencing was that when typing in a URL in the address bar, or opening a bookmark, IE was launching the default browser (which could look like a new window if IE was set as the default). Kind of cool, but not when you use apps that require IE and use popup windows 
The solution is to delete the registry key:
HKEY_CLASSES_ROOT\CLSID\{c90250f3-4d7d-4991-9b69-a5c5bc1c2ae6}
Dec 15
What is it with kids (14-18 year olds I mean, god I must be getting old!) these days. They see a bike and they feel that they must try to get you to ‘do a wheelie’ for them.
“Yes mate, OK, I’ll just chew my sprockets up and stretch my chain because you want to see a wheelie shall I? I’ll just spin my wheel up on this cold, wet road and shred my expensive tyres on your say-so. Tell you what, I’ll do a wheelie for you, even though I’m 3 feet behind a car, filtering through rush-hour traffic. No doubt you’ll forget about it 5 minutes after it’s happened, but that’s not a problem because there’ll be another biker along 5 minutes later for you to harass.”
Yes, I can do wheelies and yes, I enjoy doing them, but only when I want to do them and when it’s safe enough to do it! You want to see a wheelie every 5 minutes - You grow up, get a bike, and learn for yourself!
Dec 09
Molly E. Holzschlag, Group Lead at the Web Standards Project (WaSP) has posted an open letter (partly because their feedback system no longer works!) to Disney Store UK on her blog, regarding their recent redesign.
It seems that whoever redesigned the site doesn’t have any idea about web standards and semantic design, as all trace of the previous, well-written site, which was used as an example in numerous case studys about modern web design best practice, has gone. Instead we’re now served up a table based design that “regresses back to all the bad habits that have hurt the progress of Web development and design.”
Dec 07
Received this in my Download Squad RSS feed this morning. Norwegian developer Haakon Bertheussen has implemented an algorithm that colorises black and white photos in his own program called Recolored. The Windows beta is available to play with for free.
I downloaded and tested it with a desaturated photo and the results were amazing - on the first try! With practice I think this tool has real potential! My grandparents had a collection of old sepia toned photos that I have scanned and I can’t wait to try this out on them.
