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Submission + - IBM Researchers: Old Laptop Batteries Can Power Slums

mrspoonsi 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

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

*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

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 Suddenoutbreakofcommonsense (Score 2) 96

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.

Comment Re:I'd just as soon have a human accountable (Score 1) 305

In any event, in any device, in any change, some human needs to be responsible for it. When it comes to my car, that someone can't just be me. When it comes to my sister, it can't be her. It's that simple.

True, wrong, wrong.

I would certainly trust myself with working on a car/plane/boat that I have MY ass in/on rather than anybody else. No one in the whole world does have a better reason to take special care than I do in this case and as an "amateur" I can spend the time and have an extra deep look at everything in general or a thing that has raised my suspicion in one way or another.

And I have certainly seen dangerously bad jobs done on cars by those "professionals"...

Comment Re:I do not look forward to this. (Score 1) 336

>How about the awkward feeling that he googles you just after you talked?

>Is that slightly better?

Yes, it is. He/she is going to get a live impression of me first rather than anything else.

>If there's something bad to learn about you, you're out of luck, no matter when you are googled.

If there is something to learn, knowing me in person firsthand might make a big difference on how this is perceived. This does not have to be the sex offender list, but my profession alone might be enough. If I was a physician, perhaps I don't want to hear people's medical problems immediately. I have been in situations where people told me afterwards that they would have treated me differently if they had known immediately that I was a foreigner. Prejudice against other nationalities and all. Once they realized first that I am a fairly normal person everything was fine all the way through.

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