Two bodies in contact apply forces Fi bt and F2 == 2bt, considering very small angles, where the tendons maintain a certain tension T, and where b is a constant. Determine at what instant the tendon suffers fracture. m2 01 02 m1 F₁

Check Your Understanding Find the angle between forces F1and F3in Example 2.16.

Problems 33 and 34 are paired. One end of a uniform beam that weighs 2.80 102 N is attached to a wall with a hinge pin. The other end is supported by a cable making the angles shown in Figure P14.33. Find the tension in the cable. FIGURE P14.33 Problems 33 and 34.

Consider a nanotube with a Youngs modulus of 2.130 1012 N/m2 that experiences a tensile stress of 5.3 1010 N/m2. Steel has a Youngs modulus of about 2.000 1011 Pa. How much stress would cause a piece of steel to experience the same strain as the nanotube?

In a tug-of-war game on one campus, 15 students pull on a rope at both ends in an effort to displace the central knot to one side or the other. Two students pull with force 196 N each to the light, four students pull with force 98 N each to the left, five students pull with force 62 N each to the left, three students pull with force 150 N each to the right, and one student pulls with force 250 N to the left. Assuming the positive direction to the tight, express the net pull on the knot in terms of the unit vector. How big is the net pull on the knot? In what direction?

Review the relationship between stress and strain. Can you find any similarities between the two quantities?

(a) When water freezes, its volume increases by 9.05% (that is, V/V0=9.05102 ). What force per unit area is water capable of exerting on a container when it freezes? (It is acceptable to use the bulk modulus of water in this problem.) (b) Is it surprising that such forces can fracture engine blocks, boulders, and the like?

Find the scalar components of three-dimensional vectors G and H in the following figure and write the vectors in vector component form in terms of the unit vectors of the axes.

A person places a bathroom scale in the center of the floor and stands on the scale with his arms at his sides ( Fig. 3.26a). If he keeps his arms rigid and quickly raises them over his head (Fig. 3.26b), he notices the scale reading increases as he brings his arms upward. Why? Then, with his arms over his head (Fig. 3.26c), he quickly lowers his arms to his side. How does the scale reading change and why? (Try it yourself.)

A 20.0-kg horizontal plank 4.00 in long rests on two supports, one at the left end and a second 1.00 m from the right end. What is the magnitude of the force exerted on the plank by the support near the right end? (a) 32.0 N (b) 45.2 N (c) 112 N (d) 131 N (e) 98.2 N