Period, amplitude, maximum speed, and total energy

aligass2004

1. The problem statement, all variables and given/known data
A 175g mass attached to a horizontal spring oscillates at a frequency of 2.0Hz. At one instant, the mass is at x = 5.0cm and has Vx = -20cm/s. Determine the following.

a.) the period
b.) the amplitude
c.)the maximum speed
d.)the total energy


2. Relevant equations



3. The attempt at a solution
I solved part a by using T = 1/f = .5s. I'm not sure how I find the amplitude though. To find the maximum speed, I think I would just use Vmax = 2(pi)fA or (2 pi A)/T. I'm also not sure how I would find the total energy.