# Oscillatory motion? Does this spring have to do with oscillatory motio

1. May 28, 2014

### boii

Hi, i started to learn oscillatory motion today, and my teacher didn't teach us very well....and he told us that we were to conduct a oscillatory motion lab. So, me and a couple of other friends conducted a spring not moving that was hanged vertically and just calculated the displacement of the spring every time we added weights on it. we then used the formula of F = -KX, to find the spring constant. And i was wondering if this still counted as a oscillatory motion? I would say no since it's not moving, but my teacher seems legitimately enough to believe it counts as a oscillatory motion lab. I don't see how i can describe how this spring has a connection to oscillatory motion. So do you think it has a connection to oscillatory motion?

My data were

Mass (g)
1. 50
2. 60
3. 70
4. 80
5. 90
6. 100

Distance the spring stretched (cm)
1. 9.5
2. 10.4
3. 11.6
4. 12.5
5. 13.8
6. 14.5

Last edited: May 28, 2014
2. May 28, 2014

### ehild

That experiment was about spring force, to show that the force exerted by a stretched spring, is proportional to the change of length of the spring. And it can be shown that such force involves oscillatory motion. Just pull a bit the mass hanging at the end of the spring and it will do oscillation about the previous equilibrium point.

ehild

3. May 28, 2014

### dauto

Also, the frequency of the oscillation can be calculated from the formula $$f=\frac{1}{2\pi}\sqrt{\frac{k}{m}},$$ where k is the spring constant and m is the attached mass.

4. May 28, 2014

### boii

So if I don't pull it and let it hanging it doesn't count as oscillatory motion?

5. May 28, 2014

### ehild

When the spring and the mass hanged onto it are steady, it is not oscillatory motion. It is not motion at all.

ehild

6. May 28, 2014

### boii

So if I was to redo my lab. And I would have to pull the spring how would I measure the time?

7. May 28, 2014

### ehild

Pull the weight hanging on the spring to set it into motion. You need a stopwatch to measure the time of a few periods. The weight moves up and down, the time period is the time elapsed between two subsequent highest or (lowest) positions. Measure at least 5 periods.

ehild