A moving 4.3 kg block collides with ahorizontal spring whose spring constant is 321 N/m(see figure). The block compresses the spring a maximum distance of11.5 cm from its rest position. The coefficient of kineticfriction between the block and the horizontal surface is 0.28.
a) How much mechanical energy is being dissipatedby the force of friction while the block is being brought to restby the spring?
b) What is the speed of the block when it hits the spring?