Answer:
128.8 N/m
Step-by-step explanation:
Frequency for a spring attached oscillating mass is f=1/2π
,
where k is the stiffness of the spring (or spring constant) and m is the mass
Solving for k
f²(4
)=k/m
k=m(f²(4
))=2000(16·4·3.14²) = 1262/9.8=128.8 N/m