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

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