A student investigates the energy changes of a mass oscillating on a vertical spring, as shown in the figure below.
The student draws a graph of the variation with displacement 
of energy 
of the oscillation, as shown in the graph below.
State whether the energy represents the total energy, the potential energy or the kinetic energy of the oscillations.
The student repeats the investigation but with a smaller amplitude. The maximum value of is now found to be 
. Use the graph above to determine the change in the amplitude. Explain your working.
