Felipe´ separates the students into groups. The group farthest from the sensor
jumps in unison, followed by the next group which is a little closer, followed by the
next group, etc. When the students look at the record of the movements on the
seismograph, they see that the amplitude of the recordings are larger for the group
closest to the sensor, gradually lessening for the more distant groups, thus
demonstrating how an earthquake in California will be felt in the nearby regions,
but not, say, here in St. Louis.