
Both the springs are connected in parallel, therefore
Keq=K+K=2K
Now, time period of spring-block system is given by,
T=2πKeqm=2π2Km
Given here, m=490gm=0.49kg and K=2Nm−1
So, T=2π2×20.49
=2π40049=2π207=107π
Now, number of oscillation in 14π is
N=Ttime=107π14π=20