A way to hear the electric car coming down the road

"Close your eyes," engineering graduate student Bryan Bai called out from his Prius at the far end of the Tresidder parking lot, before the car began moving forward. A Toyota Prius runs silently on electric power until its speed exceeds 25 mph, at which point the gas engine kicks in. Unseen and unheard, Bai could be driving the vehicular version of Jaws, only without the suspenseful background music. That's a hazard for pedestrians, especially blind people.