Calculate total energy from potential at equilibrium point

1. May 2, 2014

EliteCodexer

1. The problem statement, all variables and given/known data
A block of mass 0.25 kg is connected to a spring with spring constant 35 N/m. The block is oscillating on a frictionless horizontal surface. Its speed as it passes through its equilibrium position is 1.04 m/s. What's the total energy of the system?

2. The attempt at a solution
Not sure how to find potential energy at equilibrium point given the speed as it passes through. I really just need someone to walk me through this problem.

Total Energy=Potential+Kinetic

Last edited: May 2, 2014
2. May 2, 2014

PhanthomJay

At the equilibrium point, there is no net force on the block. What does that tell you about the spring potential energy at that point?

3. May 2, 2014

EliteCodexer

there is none?

4. May 2, 2014

PhanthomJay

That is correct. The spring is at its original unstretched length at that point. So what is the total energy at the equilibrium point in this example?

5. May 2, 2014

EliteCodexer

what about the kinetic energy though?

6. May 2, 2014

PhanthomJay

The total energy of the system is constant at at any point in time and equal to the sum of the kinetic and potential energies at any point in time. The total energy of the system at the equilibrium point is thus????? and thus the total energy of the system at any point is????