Answer :
Final answer:
The ideal critical additional displacement is -0.29 m; however, since this is not an option and it implies the tower should already be at the verge, there is no displacement required for the Tower of Pisa to be at the tipping point with the given model.The correct answer is B. 1.23 m
Explanation:
The leaning Tower of Pisa will be at the verge of toppling when its center of gravity is directly above the edge of its base. To determine this critical displacement, we must consider the tower's current displacement and its radius. Since we treat the tower as a uniform cylinder, its center of gravity is at its geometrical center, halfway in its diameter. The maximum displacement at the top before toppling can occur would be equal to the tower's radius. The critical displacement at the top is thus the tower's radius minus the current displacement.
The radius of the Tower of Pisa is half of its diameter, which is 7.44 m / 2 = 3.72 m. The current displacement is 4.01 m. Therefore, the additional displacement needed to reach the critical point is 3.72 m - 4.01 m = -0.29 m. Since we are interested only in absolute value for the displacement needed, the direct answer in two words is: 0.29 m. But since this is not an option and the current displacement is already beyond the half of the diameter, it suggests the tower should already be at the verge of toppling based on the idealized model. Thus, no additional displacement is required; it's already at the critical state according to the simple physical model we used.
