What will be the force constant of the spring system shown in fig. (7)
k12+k2
12k1+1k2−1
12k1+1k2
2k1+1k2−1
Two spritrgs of force constants k1 and k2 are in parallel. Hence k′=k1+k1=2k1 The third spring is il series with spring of force constant k ∴ 1k=12k1+1k2 or k=12k1+1k2−1