What is the spring constant for the spring?

[songminho]

Homework Statement

A mass 2.74 kg is hung from a spring. The mass is pulled down a short distance and released, it oscillates with a frequency f = 1.972 Hz.

What is the spring constant for the spring?

Homework Equations

f=1/2pi*sqrt(k/m)

The Attempt at a Solution

1.972 = 1/2pi*sqrt(k/2.74)
Rearranged:
k = (1.972/ 1/2pi)^2 x 2.74
= 4.3184 N/m

But this answer is wrong? Can someone please show me how this is so? Thank you

 

[paisiello2]

What's the definition of Hertz?

 

[Doc Al]

k = (1.972/ 1/2pi)^2 x 2.74

Redo your calculation a bit more carefully.