A mass-on-a-spring system has
m = 54 kg and k = 225 N/m.
The mass is pulled a distance 0.25 m from its equilibrium position and then released.
(a) What is the maximum acceleration of the mass?
My work: F=ma -kx=ma
(225)(.25)=(54kg)(a)
solve for a. a=1.04 m/s^2. this is correct
(b) What is its maximum velocity?
I'm not really sure how to start this. I know that max velocity is equal to amplitude times sqrt(k/m), but I do not know the amplitude. Please help.