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Comment Re:Short yellow lights are a safety hazard (Score 1) 507

Actually, the mass of the vehicle doesn't really significantly impact the stopping distance on reasonably level grade.

See here.

Actually it does. There's a vastly different co-efficient of friction between the road and a semi vs. a car. Tyre compounds, center of mass and probably the most significant difference being how well the suspension keeps the tyres in contact with the road. The heavier the "unsprung mass" (all the components between the dampers/springs and the road) the more intertia and the less quickly the suspension will keep the tyres in contact. Trucks have very heavy suspension in comparison to a car, making them worse at stopping.

Comment Re:There's nothing spectacular about the Rotary (Score 1) 359

I beg to differ, rotary engines are easily the best design of the non reciprocating pistons and I don't think you're being fair to them.

Even if it was altogether true that they needed rebuilds that often it's still better than otto engines were doing at the same period in their development. Ditto for the fuel efficiency. While it is true that the higher output turbo engines can need rebuilds that often, I've heard of the naturally aspirated engines regularly running to 200-300k miles without a rebuild - and these motors still make around 100bhp/litre so they're reasonably stressed engines.

Comment Re:Golf Diesel (Score 1) 576

I take offence to this. There are plenty of cars both in Europe and the States (and beyond) that are low powered by anyone's definition. The choice is there, and a reasonable statement is that a lower powered car will be cheaper. People can choose these cars if they wish. However, if they don't why does this amount to gross denial - and who are you to dictate someone's requirements to them? It's a perfectly valid argument that a more powerful car makes certain situations safer - this doesn't amount as you say to someone arguing that they can't drive on the freeway.

Also a Euro is a unit of currency, when you call me one it conjures an image of a die-hard republican spouting about commies - except the polar opposite. Although no less ignorant.

Comment Re:How? (Score 1) 317

A certain amount of negative camber is actually beneficial in the situation you describe. As you hit the brakes, the front of the car squats, which compresses the suspension which changes it's geometry. Generally under compression, this geometry change results in positive camber, or the tyres tops pointing outwards. If the tyres were cambered negatively beforehand, under squat the tyres approach a parallel state with the road below (assuming it's level).

Designing suspension geometry is an exercise in compromise. The question here is do you want your tyres parallel with the road under compression or not. Since under compression you're generally in a situation where you're testing the tyre's grip, it seems to me that a degree or 2 of negative camber is actually ideal.

Biotech

First Halophile Potatoes Harvested 117

Razgorov Prikazka writes "A Dutch-based company from Groningen is trying to create a potato race that is able to survive in a saline environment. The first test-batch was just harvested (English translation of Dutch original) on the island Texel and seem to be in good shape. The company states that rising sea-levels will create a demand for halophile crops. I do wonder if one still has to put salt on ones potatoes when they are grown in salt water."
Biotech

Part-Human, Part-Machine Transistor Devised 77

asukasoryu writes "Man and machine can now be linked more intimately than ever, according to a new article in the journal ACS Nano Letters. Scientists have embedded a nano-sized transistor inside a cell-like membrane and powered it using the cell's own fuel. To create the implanted circuit, the UC scientists combined a carbon nanotube transistor, lipid bilayer coating, ion pump, and ATP. The ion pump changes the electrical charge inside the cell, which then changes the electrical charge going through the transistor, which the scientists could measure and monitor."
Science

Quantum State Created In Largest Object Yet 265

SpuriousLogic writes "A team of researchers have created a 'quantum state' in an object billions of times larger than ever before. From the article: 'Such states, in which an object is effectively in two places at once, have until now only been accomplished with single particles, atoms and molecules. In this experiment, published in the journal Nature, scientists produced a quantum state in an object billions of times larger than previous tests. The team says the result could have significant implications in quantum computing.'"

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