As the figure shows, a 2.6 kg block is accelerated by a compressed spring whose spring constant is 540 N/m. After leaving the spring at the spring's relaxed length, the block travels over a horizontal surface with a coefficient of kinetic friction of 0.25 for a distance L = 7.8 m before stopping. What is the increase in the thermal energy of the block-floor system? 49.6 J. What is the maximum speed of the block? m/s. Through what distance is the spring compressed before the block begins to move? 42.8 cm.