Standard +0.8 This is a multi-step energy conservation problem requiring careful consideration of three phases (free fall, elastic extension, and air resistance throughout). Students must set up and solve a quadratic equation involving gravitational PE, elastic PE, and work against resistance. While the method is standard for Further Mechanics, the bookkeeping and algebraic manipulation elevate it above routine questions.
1 A bungee jumper of mass 80 kg steps off a high bridge with an elastic rope attached to her ankles. She is assumed to fall vertically from rest and the air resistance she experiences is modelled as a constant force of 32 N . The rope has natural length 4 m and modulus of elasticity 470 N .
By considering energy, determine the total distance she falls before first coming to instantaneous rest.
1 A bungee jumper of mass 80 kg steps off a high bridge with an elastic rope attached to her ankles. She is assumed to fall vertically from rest and the air resistance she experiences is modelled as a constant force of 32 N . The rope has natural length 4 m and modulus of elasticity 470 N .
By considering energy, determine the total distance she falls before first coming to instantaneous rest.
\hfill \mbox{\textit{OCR Further Mechanics 2021 Q1 [6]}}