Final answer:
An unsupported concrete wall struck near its top with a wrecking ball is likely to fall over by rotating at its base due to greater torque. When still, a wrecking ball has potential energy; if released, it converts this into kinetic energy during its swing.
Step-by-step explanation:
If a wrecking ball hits an unsupported concrete wall near the top, it is much more likely to cause the wall to fall over by rotating at its base rather than falling straight down. This is due to the fact that when an object is struck at a point far from its pivot (in this case, the base of the wall), it generates a larger torque which promotes rotational motion. The leverage effect enables a force applied at a distance from the pivot to be more effective at turning or tipping the object. If the wall is hit at the base with the same force, how it falls will depend on how firmly attached it is at the base. A well-secured wall might still crack and crumble, while a loosely attached wall might tip over more readily.
When considering a wrecking ball that is motionless, it is still associated with energy. This form of energy, called potential energy, is related to the position of the wrecking ball and the force of gravity acting on it. If the ball is released, the potential energy will be transferred into kinetic energy as the wrecking ball accelerates downward and swings. At the highest point of its swing, the ball has maximum potential energy and as it swings down, this energy is converted into kinetic energy, which is at its maximum at the lowest point of the swing.