# Oscillator Problem Maximum speed & amplitude

1. Dec 9, 2011

### jjd101

1. The problem statement, all variables and given/known data
A 800g oscillator has a speed of 120.0 cm/s when its displacement is 1.5 cm and 55.0 cm/s when its displacement is 8.0 cm.

a. What is the oscillator’s maximum speed?

b. What is the oscillator’s maximum amplitude?

2. Relevant equations

A= sqroot(X^2+(V^2/w^2)
Vmax=wA

3. The attempt at a solution

I attempted to find the angular frequency but even with w=sqroot(k/m) i couldnt find a way to solve for w

2. Dec 9, 2011

### Staff: Mentor

Write expressions for the total energy for the two known points (sum of PE and KE). There will be a single unknown to solve for. After that you should be able to continue.

Conservation of energy is a powerful tool for these type of problems.

3. Dec 9, 2011

### jjd101

i did this and solved for the Spring constant since this is what is not given and got K=147.4 ? correct ?

4. Dec 9, 2011

### Staff: Mentor

Yup. You should be able to continue "as usual" from here.

5. Dec 9, 2011

### jjd101

I did this and got max velocity as 121.7cm/s and max amplitude as 8.97cm. right?