A3.5 kg block is accelerated from rest by a compressed spring of spring constant 640 n/m. the block leaves the spring and then travels over a horizontal floor with a coefficient of kinetic friction 0.25. the frictional force stops the block in distance d=7.8 m. 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?

66.944 Joules

66.944 Joules

0.457 m

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration

g = Acceleration due to gravity = 9.81 m/s²

k = Spring constant = 640 N/m

m = Mass of block = 3.5 kg

x = Compression

Increase in thermal energy is 66.944 Joules

Kinetic energy of the block is 66.944 Joules

Original compression of the spring is 0.457 m

i guess it’s a and b

i don't know that i agree with that but what's the question ?