A block with a mass of 2.85 kg is hung by a vertical spring of stiffness 13.3 kg/s2. The damping force is given by -b(dx/dt)m where b = 364 g/s. The block is pulled down 12 cm and then released.

Question

(a) Calculate the time required for the amplitude of the resulting oscillations to fall to 45 % of the initial amplitude.

(b) How many full oscilltions are made by the block in this time?

Answer 1

stiffness must be force/distance, for example Newtons/meter. kg is mass, not force and I have no idea what s2 means.

similarly b *dx/dt would be a force in Newtons where b would have units Newtons seconds/ meters