Physics
posted by Cameron .
Need help on part B!
A 2.50 mass is pushed against a horizontal spring of force constant 26.0 on a frictionless air table. The spring is attached to the tabletop, and the mass is not attached to the spring in any way. When the spring has been compressed enough to store 15.0 of potential energy in it, the mass is suddenly released from rest.
a. Find the greatest speed the mass reaches? (Answer: 3.46 m/s)
b. What is the greatest acceleration of the mass?

The greatest acceleration is w^2 times the maximum deflection.
w is the angular frequency, which equals k/m
You have not provided dimensions for you numbers, so that is all the help you are going to get.
Learn the importance of dimensions with the numbers you use in physics, or don't expect to pass the course. 
Sorry, it was an accident. Geesh. It didn't copy and paste correctly.