a mass is suspendung at the end of spring of length L and stiffness s . if the mass of the spring is m amd the velocity of an element dy of its length is proportional to its distances y from the fixed end of spring show that the kinatic energy of this element is
(m/L * dy) *(y/L*v) مضروبه ب 1/2
v : velocity
m: mass
by integrating over the length of the spring show that its kinatic energy is 1/6mv and from oscillating system that the frequency
w^2 = s/ M+(m/3) p