A long strip of springy steel is clamped at one end so that the strip is vertical. A mass of 
is attached to the free end of the strip, as shown in the figure below.
The mass is pulled to one side and then released. The variation with time 
of the horizontal displacement of the mass is shown in the graph below.
The mass undergoes damped simple harmonic motion.
Explain what is meant by damping.
Suggest, with a reason, whether the damping is light, critical or heavy.
