G Barnes (Am Journal of Physics, 1958,vol26, p7) defines coefficint of=
restitution as follows:
e=3D (ae1 +be2)/(a+b)
e1 and e2 are Young coefficient of colliding bodies 1 and 2.=20
a and b are realtive hardness of substances 1 and 2.=20
How establish and explain the dependance of the coefficient of restitution=
upon the hardness of bodies?
What is the link between hardness and rebound?=20