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Comment Re:A linear induction motor is not a railgun. (Score 3, Informative) 314

To accelerate a 100000 pound object to 240 mph requires an energy of 260 MJ (sorry I converted all units to SI before I started calculating so you have to convert it back to BTU or kcal or whatever the right unit for energy you want to use yourself). Assuming a linear acceleration over 300 feet to 240 mph gives an acceleration time of 1.7 s. This results in an average power of 153 MW. AFAIK there is no electrical turbine that will supply an extra 153 MW at the flip of a switch. Electrical energy has to be stored somewhere to let the catapult work.

Nyh

Submission + - It's life Jim but not as we know it, (nasa.gov)

Nyh writes: NASA will hold a news conference at 2 p.m. EST on Thursday, Dec. 2, to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life. Astrobiology is the study of the origin, evolution, distribution and future of life in the universe.

Comment Get a Canon with CHDK (Score 1) 106

A large portion of the canon cameras support CHDK (canon hack devkit). One of the nice features included in this is motion detection. This requires no external components to get it working, as it uses the CCD for triggering. There are numerous scripts that use CHDK to implement delays, time laps photo sequences or other funky actions. Most of the supported cameras are fast enough to capture lightning.

Comment Re:neat (Score 1) 146

They run at gigahertz speeds, which implies nanosecond timings. A flywheel with decent mass spinning a million RPM is only four orders of magnitude away from the speed of light.
It all depends.

Speed of light: 300e6 m/s
Speed of micrometer scale graphene flakes spinning at 60 million rpm:
2*pi*1e-6/1e-6 = 6 m/s = 21.6 km/h
I think you can get any material spinning at 60 million rpm at micrometer scale. Tensile strength is not very important at these speeds.

It is a nice trick though.

Nyh

Comment Re:Openfietskaart.nl (Score 1) 119

At the moment I think it's aimed at typical commuting distances. 360 km is a very long ride! (How long does that take?!)

Actually it is close to 400 km (A120, A12, London city center, A4, A30, A303). My best time is 14 hours, worst 20 hours. For the return journey I allot 24 hours because I don't want to miss the ferry. But 400 km isn't that a big distance when you train for rides like Paris-Brest-Paris or London-Edinburgh-London.

Nyh

Comment Re:Openfietskaart.nl (Score 2, Informative) 119

Even in the Netherlands we do not have a satnav app for cyclists on the iPhone. Route for cyclists can be done by the excellent 'fietsrouteplanner' planner from the Fietsersbond (http://www.fietsersbond.nl/fietsrouteplanner/fietsroutes-vandeurtotdeurplanner/index.html). This great planner has lots of options and biker profiles (like shortest route, avoid busy traffic, green route, social safe route, racing cyclist, etc.) but once you are cycling it is quite useless. The route is static, has no rerouting when you choose an other route due to roadworks or just because you felt so.

I immediately tried out this app but was a bit disappointed. I cannot plan a route from Harwich to Exeter, a route I have cycled multiple times to visit family in England.

Nyh

Comment Unfortunately (Score 4, Insightful) 111

It'll cool your feet in the winter when it works at its best and in the summer the difference between warm sidewalks and the inside of the boot will not generate any electricity. This means that when you don't mind to wear it, it does not work. When it works, it causes so much discomfort that you choose not to... Mmm.

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