A spring with a wire diameter of 1mm and 20 turns of radius 10 mm was given to you. The weight of the spring is 4 g.
(a) When the spring is loaded vertically with 1 kg weight, it is extended by 30 cm. When the weight is removed, it comes back to its original shape. Find Young's modulus (E) of the material. Assume Poisson's ratio is 1/3.
(b) What is this spring made of?