The mathematician and the pea

You have ten cans of peas. The cans are open. In each can, there are 100 peas. In 9 of the ten cans, each pea weighs 1 gram. In the tenth can, each pea weighs only .9 grams. You do not know which can has the smaller peas, nor is it possible to tell with the naked eye. To help you, you have an electronic scale. However, the scale is not in great shape, and can only provide one correct measurement before permanently malfunctioning. How can one, using only the one measurement afforded by the scale, determine beyond a shadow of a doubt which can it is that has the smaller peas? Submitted by Chris Timmel.