Final answer:
A stress-strain plot shows the relationship between stress and strain for a material under a load. It helps us understand the material's behavior and determine the yield strength.
Step-by-step explanation:
A stress-strain plot shows the relationship between stress (force per unit area) and strain (fractional elongation) for a material under a load. It helps us understand the material's behavior under different loads, including its elasticity and plastic deformation limits. From such a plot, we can determine the yield strength of the material, which is the point at which plastic deformation begins. However, we cannot determine the value of Planck's constant or the work function of the metal from this plot.