Howdoes the huge ball `( 5.4 xx 10^(5) kg )` hanging on the `22^(nd)` floor of one of the world's tallest building ( chapter opening question mentioned in the introduction) counter the sway of the building?

Explanation

Thehuge ball hangs from four cables and swings like a pendulum when the building sways. When the building sways-say, westward-the ball does also but delayed enough so that asif finally swings westward, the buildingis swaying eastward. So, the motion of the ball is out of step with the builiding motion, and thus counters it.