Suspension cables are used to carry gondolas at ski resorts. (See Figure 5.14) Consider a suspension cable that includes an unsupported span of 3020 m. Calculate the amount of stretch in the steel cable. Assume that the cable has a diameter of 5.6 cm and the maximum tension it can withstand is 3.0 × 10⁶ N.

Strategy

The force is equal to the maximum tension, or F = 3.0 x 10⁶ N. The cross-sectional area is Πr² = 2.46 x 10^-3 m. The equation  can be used to find the change in length.