At speeds above 18.6 mph, both gasoline and electric cars generate noise from wind resistance and tires. But below that threshold, electric vehicles are often silent, which is why the new U.S.

By Sam Felsing, AUG 26, 2010 2:37 am PDT. At a glance. Pros. Cons. Our Verdict. ... Its free iPad offering, Discover—Wikipedia in a Magazine takes content from the online, ...