A diving board 3.00 m long is supported at a point 1.00 m from the end, and a diver weighing 500 N stands at the free end (Fig. E11.11). The diving board is of uniform cross section and weighs 280 N.
Find (a) the force at the support point.

(III) Two wires run from the top of a pole 2.6 m tall that supports a volleyball net. The two wires are anchored to the ground 2.0 m apart, and each is 2.0 m from the pole (Fig. 12–70). The tension in each wire is 125 N. What is the tension in the net, assumed horizontal and attached at the top of the pole?

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(II) A heavy load M g = 62.0 kN hangs at point E of the single cantilever truss shown in Fig. 12–81.

(a) Use a torque equation for the truss as a whole to determine the tension F_T in the support cable, and then determine the force F→_A on the truss at pin A. Neglect the weight of the trusses, which is small compared to the load.

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The roof over a 9.0-m x 10.0-m room in a school has a total mass of 12,400 kg. The roof is to be supported by vertical wooden “2 x 4s” (2 x4 in inches, but actually about 4.0 x 9.0 cm) equally spaced along the 10.0-m sides. How many supports are required on each side, and how far apart must they be? Consider only compression, and assume a safety factor of 12.

A board 8 m in length, 20 kg in mass, and of uniform mass distribution, is supported by two scales placed underneath it. The left scale is placed 2 m from the left end of the board, and the right scale is placed on the board's right end. A small object 10 kg in mass is placed on the left end of the board. Calculate the reading on the left scale. (Use g=10 m/s².)

BONUS:Calculate the reading on the right scale.

(II) A shop sign weighing 215 N hangs from the end of a uniform 135-N beam as shown in Fig. 12–59. Find the tension in the supporting wire (at 35.0°), and the horizontal and vertical forces exerted by the hinge on the beam at the wall.

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(III) Two wires run from the top of a pole 2.6 m tall that supports a volleyball net. The two wires are anchored to the ground 2.0 m apart, and each is 2.0 m from the pole (Fig. 12–70). The tension in each wire is 125 N. What is the tension in the net, assumed horizontal and attached at the top of the pole?

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