4.5 Normal, Tension, and Other Examples of Forces

A cable raises a mass of 120.0 kg with an acceleration of 1.3 m/s2. What force of tension is in the cable?

Two teams are engaging in a tug–of-war. The rope suddenly snaps. Which statement is true about the forces involved?

1. The forces exerted by the two teams are no longer equal; the teams will accelerate in opposite directions as a result.
2. The forces exerted by the players are no longer balanced by the force of tension in the rope; the teams will accelerate in opposite directions as a result.
3. The force…

Two teams of nine members each engage in a tug of war. Each of the first team’s members has an average mass of 68 kg and exerts an average force of 1350 N horizontally. Each of the second team’s members has an average mass of 73 kg and exerts an average force of 1365 N horizontally. (a) What is magnitude of the acceleration of the two teams? (b) What is the tension in the section of rope between t…

(a) Calculate the tension in a vertical strand of spider web if a spider of mass $8 . \text{00} \times \text{10}^{- 5} \text{ kg}$ hangs motionless on it. (b) Calculate the tension in a horizontal strand of spider web if the same spider sits motionless in the middle of it much like the tightrope walker in the figure. The strand sags at an angle of $\text{12}º$ below the horizontal. Compare this with the tension in the vertical strand (find their ratio).

Show that, as stated in the text, a force $\textbf{F}_{\bot}$ exerted on a flexible medium at its center and perpendicular to its length (such as on the tightrope wire in the figure) gives rise to a tension of magnitude $T = \frac{F_{\bot}}{2 \text{sin} \left(\theta\right)}$.