Anyone with a little common sense will realize that the top of a building does not pass through the concrete and steel that comprises the lower portion of the building at the same rate that it falls through air. This just doesn't happen, unless, of course, the lower part of the building has lost its structural integrity (and this is usually due to the detonation of a multitude of small explosive charges as seen in controlled demolitions).
.... Compare falling through air with falling through steel and concrete - 9/11 Physics TruthThe Towers' Tops Fell Without Resistance.
The towers fell at near the speed of a falling object encountering no resistance. It is generally accepted that both towers fell completely in little more than 10 seconds -- only slightly longer than would take an object in free-fall to fall the towers' height. But unless the intact portion of the building were demolished before the falling portion encountered it, it would have greatly slowed the fall, as the kinetic energy of the falling
