Two light springs A and B have force constants k and 2k respectively. Their upper ends are fixed to a rigid support, while their lower ends are tied together to carry a single mass m so that the springs act in parallel.
(i) Obtain an expression for the effective force constant keff of the combination.
(ii) Derive an expression for the natural angular frequency of vertical oscillation of the mass in terms of k and m.
(iii) If k=120Nm−1 and m=0.50kg, calculate the natural frequency of the system.