## Define following terms of spring:

(i) Spring rate: The spring rate is defined as the load required per unit deflection of the spring. It is also

known as spring stiffness or spring constant. Mathematically,

Spring rate, k = W / δ

Where,

W = Load

δ = Deflection of the spring

(ii) Spring index: The spring index is defined as the ratio of the mean diameter of the coil to the

diameter of the wire. Mathematically,

Spring index, C = D / d

Where,

D = Mean diameter of the coil

d = Diameter of the wire