Answer Happy

Q2. (a) The central deflection x of a trampoline (Fig. Q2) is related to the impact force F by the equation: F=kx?, where the spring constant k=6000 N/m². Following a deflection Xo, the trampoline propels a child (treated as a particle, and of mass 40 kg) upwards to a height of 1.5m above the equilibrium position. (i) Derive an equation which relates the stored strain energy Es of the trampoline to the deflection, x. [3] (ii) Write down the general principle (equation) which relates two mechanical energy states, defining each of the terms. [3] (iii) Hence, determine the deflection, Xo [4] Note: In part (iii), a “trial and error” solution may be necessary. In that case, an answer to the nearest 0.1m will be sufficient.