H/a=6/ r/H=0.40 theta<30-35 deg FIG. 9: The second toy model made with plastic blocks. The structure appears to break at f=0.40, and at a larger angle 0 a 300-350, which can be estimated by measuring the angle formed by the upper part of the tower with the vertical measuring the angle the upper part of the chimney forms with the vertical direction. Th is in good agreement with the position of the maximum for the solid-10o curve in Fig. 6 and also with the data of Fig. 7, using the H=20 curve, showing that the theory is applicable also to these small-scale models Our second example is a taller tower(H= 1.9 m, m=0.65 kg, and H=61)made with 100 plastic blocks of a very popular brand of toy bricks. The blocks are inserted on top of each other so that bending of the structure is allowed, but shear stress cannot possibly break the tower. The 100 toy blocks are arranged by color to subdivide the structure into three equal parts, and also the position of the center is marked. This time the rupture occurs for an angle around 0 2 300-35, and at the height ratio f=0.40. This is consistent with the 30 solid curve in Fig. 6, while the data from Fig. 7(for H=60)would suggest a smaller angle of rupture. It is actually difficult, with this type of toy bricks, to estimate the angleFIG. 9: The second toy model made with plastic blocks. The structure appears to break at r H = 0.40, and at a larger angle θ ≃ 30◦ − 35◦ , which can be estimated by measuring the angle formed by the upper part of the tower with the vertical. measuring the angle the upper part of the chimney forms with the vertical direction. This is in good agreement with the position of the maximum for the solid-10◦ curve in Fig. 6 and also with the data of Fig. 7, using the H a = 20 curve, showing that the theory is applicable also to these small-scale models. Our second example is a taller tower (H = 1.9 m, m = 0.65 kg, and H a = 61) made with 100 plastic blocks of a very popular brand of toy bricks. The blocks are inserted on top of each other so that bending of the structure is allowed, but shear stress cannot possibly break the tower. The 100 toy blocks are arranged by color to subdivide the structure into three equal parts, and also the position of the center is marked. This time the rupture occurs for an angle around θ ≃ 30◦ −35◦ , and at the height ratio r H = 0.40. This is consistent with the 30◦ solid curve in Fig. 6, while the data from Fig. 7 (for H a = 60) would suggest a smaller angle of rupture. It is actually difficult, with this type of toy bricks, to estimate the angle 16