In Fig. 8-78, a 3.5 kg block is accelerated from rest by a compressed spring of spring constant 640 N/m. The block leaves the spring a the spring's relaxed length and then travels over a horizontal floor with a coefficient of kinetic friction `mu_(g)=0.25`. The frictional force stops the block in distance `D=7.8m`. What are (a) the increase in the thermal energy of the block-floor system, (b) the maximum kinetic energy of the block, and (c) the original compression distance of the spring ?

Answer

(a) 67 J ; (b) 67 J ; (c) 0.46 m