rotation of the earth

Time for another Fermi problem. There was a recent story in Science News that talked about the effects of the Chilean quakes on the Earth's rotation. The basic idea is that some ginmourmous amounts of rock moved closer to the Earth's center. Since the angular momentum of the Earth is conserved, the angular rotation rate would increase. The estimated change of the day was by about 1.26 microseconds. Could all the cars in the USA be used to change the rotation of the Earth? Well, I shouldn't have phrased the question that way. Of course 1 car technically is all you need to change the…