Passage V

If an object is at rest and the sum of the forces acting on it is zero, the object is in a state of static equilibrium. In each trial of 2 experiments on static equilibrium, 3 cables and a cylinder were arranged as shown in Figure 1.

Cables 1, 2, and 3, each with its own tensiometer (a device used to measure tension), were joined with a single knot, The free ends of Cables 1 and 2 were attached to an L-shaped support, and a cylinder of mass M was suspended from the free end of Cable 3. Cable 1 made an angle with the top of the support, and Cable 2 made a 90° angle with the side of the support. None of the cables stretched under tension. The tension forces acting on the knot, which was in static equilibrium, are shown in Figure 2.

The tension in Cable 1, , had a horizontal component, and a vertical component, · The tension in Cable 2, , was purely horizontal, and the tension in Cable 3, , was purely vertical.

Experiment 1

In Trials 1-5, M was 1.0 kg and 0 was varied. Table 1 lists , in degrees, as well as , , , and , each in newtons (N), for each trial.

Experiment 2

In Trials 6-10, M was varied and was 50°. Table 2 lists M as well as , , , and for each trial.

29. Suppose that Cable 2 was attached to the L-shaped support using a bracket that has a maximum tension rating of 51 N (meaning that it is unsafe to assume that the bracket can support forces greater than 51 N). Based on the results of the experiments, was it safe to use this bracket?

Answer and Explanation

Your Answer is

Correct Answer is C

Explanation

T2 represents the tension on table 2, so look at the T2 column of tables 1 & 2, and find that the largest T2 is 55.6 N, which exceeds the 51N given in the question stem, so the bracket will not be able to support Cable 2 at this time, use Not safe