A 1.35-kg object is attached to a horizontal spring of force constant 2.5 N/cm. The object is started oscillating by pulling it 6.0 cm from its equilibrium position and releasing it so that it is free to oscillate on a frictionless horizontal air track. You observe that after eight cycles its maximum displacement from equilibrium is only 3.5 cm.

(a) How much energy has this system lost to damping during these eight cycles?

(b) Where did the “lost” energy go? Explain physically how the system could have lost energy.