Here's what some electric vehicles will sound like to warn pedestrians

The American rock band Linkin Park is helping Mercedes-AMG come up with just the right sound for its electric performance car.

That's not a joke. At the Geneva Motor Show earlier this month, Mercedes executives said the music group would develop the sound the normally quiet battery-powered vehicles would make when driving to alert pedestrians.

That's because electric vehicles are pretty much silent, and dangerously so, regulators say. Think about your cellphone or other electronic device — you don't hear much noise coming from it when it's on and running. Now think about your gas-powered car and all the vrooms, hissing, and revs it makes when the engine is on. An EV is more cellphone-like than you'd think. Read more...