Abungee cord is essentially a very long rubber band that can stretch up to four times its unstretched length. however, its spring constant varies over its stretch [see menz, p. g. "the physics of bungee jumping." the physics teacher (november 1993) 31: 483-487]. take the length of the cord to be along the x-direction and define the stretch x as the length of the cord l minus its un-stretched length l0 ; that is, x = l − l0 (see below). suppose a particular bungee cord has a spring constant, for 0 ≤ x ≤ 4.88 m , of k1 = 204 n/m and for 4.88 m ≤ x , of k2 = 111 n/m. (recall that the spring constant is the slope of the force f(x) versus its stretch x.)

(a) what is the tension in the cord when the stretch is 16.7 m (the maximum desired for a given jump)?

(b) how much work must be done against the elastic force of the bungee cord to stretch it 16