The 9 kg block is then released and accelerates
to the right, toward the 2 kg block. the
surface is rough and the coefficient of friction
between each block and the surface is 0.5. the
two blocks collide, stick together, and move
to the right. remember that the spring is not
attached to the 9 kg block.
find the speed of the 9 kg block just before
it collides with the 2 kg block.
answer in units of m/s.