(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A mass of 1.5 kg oscillates vertically at the end of a lightweight spring. The spring has a spring constant of 145 newtons per meter. The amplitude of the motion is 8.00 cm. From this data, complete the table below.

I have to find velocity, acceleration, elastic potential energy, etc. at given points from the equilibrium point.

These points are 8 cm, 6cm, 4cm, 2 cm, 0 cm (equilibrium),... -8 cm

2. Relevant equations

Elastic Potential= 1/2kx^2

KE=1/2mv^2

GPE=mgh

3. The attempt at a solution

Someone told me that the X you plug into 1/2kx^2 is not the distance from equilibrium in the table. They said that you use the formula F=-kx.

In this case, F=mg so mg=-kx

you solve for X, and this becomes your new equilibrium point.

Then you go through and adjust the rest of the distances from equilibrium so that the closest ones to equilibrium (2 cm previously) are now 2 cm away from this new X.

And this new X is the one you plug into 1/2kx^2 to solve for elastic potential.

Is this correct?

And what values would I use for h to solve for GPE?

Using the X (distance from equilibrium) values given in the table would result in some negative GPE...

Do I make the lowest point equal to 0 cm, and adjust the rest to their distance from the lowest point?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Oscillations and Elastic Potential Energy

**Physics Forums | Science Articles, Homework Help, Discussion**