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Comment: Re:Cultural Shift (Score 1) 840

Now that's illogic. How would you have inherited your aptitute to fix things from your dad if you weren't down in the basement with him ? Genetically ???

I rather teach my kids basic but sufficient swimming capabilities and spend the rest of our time on something intellectually more challenging like, say, repairing broken stuff. I'll spare my 'useless sports skills' vs. 'being constructive in any way' rant for tomorrow...

+ - IBM Researchers: Old Laptop Batteries Can Power Slums

Submitted by mrspoonsi
mrspoonsi (2955715) writes "Old laptop batteries still have enough life in them to power homes in slums, researchers have said. An IBM study analysed a sample of discarded batteries and found 70% had enough power to keep an LED light on more than four hours a day for a year. Researchers said using discarded batteries is cheaper than existing power options, and also helps deal with the mounting e-waste problem. The concept was trialled in the Indian city of Bangalore this year. The adapted power packs are expected to prove popular with street vendors, who are not on the electric grid, as well as poor families living in slums. The IBM team created what they called an UrJar — a device that uses lithium-ion cells from the old batteries to power low-energy DC devices, such as a light. The researchers are aiming to help the approximately 400 million people in India who are off grid."

Comment: sub-100$ ?!? (Score 1) 182

by feufeu (#48028421) Attached to: HP Introduces Sub-$100 Windows Tablet

Could we please, at least on this site where people are supposed to have at least little better clue of mathematics than the average population, round prices intelligently and not fall for that bloody '99$ is not 100 !" ?!?

I don't think that anyone would use the exact price tag for a laptop of, say, 699$ rather than 700$...

So, this is a 100$ tablet for all practical purposes and now get off my lawn you stupid advertisement goons !

Comment: Re:yeah, I messed up the words (Score 1) 127

by feufeu (#48015685) Attached to: Sierra Nevada Corp. Files Legal Challenge Against NASA Commercial Contracts

*g* No, it's not balanced by the centrifugal force, since the centrifugal force doesn't exist. If it was balanced, the sum of both forces would be zero and the trajectory of the rocket/satellite/whatever would be straight. Turning means that you must have a force which in turn provides an acceleration which in turn changes the velocity vector. In the case of a circular orbit the velocity vector will only change it's *direction* due to the force, but not it's *value*, since both are at a right angle to eahc other all the time.

Comment: Re:in space, you cannot turn? (Score 1) 127

by feufeu (#48015379) Attached to: Sierra Nevada Corp. Files Legal Challenge Against NASA Commercial Contracts

Ok, to be a little clearer:

The centripetal force to stay in orbit around the earth (and this is also needed for any circular (or curved) movement BTW) is provided by the gravitational pull of the moon/earth, e.g. the gravitational force.

Again, the force is directed towards the center of the (circular) orbit, hence the name centriPETAL.

Comment: Re:gravity equal and opposite to centripital force (Score 1) 127

by feufeu (#48012621) Attached to: Sierra Nevada Corp. Files Legal Challenge Against NASA Commercial Contracts

You got it almost right.

Centripetal force IS gravity.

The centripetal force that is needed for any circular (or curved) movement is provided by the gravitational pull of the moon/earth, e.g. the gravitational force. They are not opposite to each other.

Comment: Suddenoutbreakofcommonsense (Score 2) 96

by feufeu (#48012571) Attached to: Mobile Phone Use Soon To Be Allowed On European Flights

Sadly the tag has vanished from ./ quite a long time ago or the editor forgot to put it here today.

Considering how many people foget to switch their phone off every day and how much reception of texts or data packets takes places while it's in their pocket, I've always foud it quite astounding that obviously no plane has aver fallen from the sky and it was still considered being a security risk...

That said, social aspects of the issue set aside.

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