Finding Spring Constant for Oscillating Mass

[Saladsamurai]

A 2.0kg mass attached to a spring makes 10 oscilations in 21.6s; its amplitude is .0320m

Find spring constant k. My question about this part is
frequency=(#of oscillations)/(#of seconds to complete) right?

So f=10/21.6s =2.16Hz?

So if $$k=m\omega^2$$
$$k=2(2\pi*2.16)^2$$
IT's the wording that gets me...

And to find speed at x=o I use conservation of mech energy

$$\frac{kx_m^2}{2}=\frac{mv^2}{2}+\frac{kx^2}{2}$$

and I can eliminate .5kx^2 since x=0...

 

[learningphysics]

10/21.6 is not 2.16 (that's 21.6/10).

Other than that, your work looks right.

 

[Saladsamurai]

10/21.6 is not 2.16 (that's 21.6/10).

Other than that, your work looks right.

Wow...I'm a tool...

Thanks!