Help with science experiment on strings.

[Rapidstatique]

Okay, so I'm doing this science experiment. It's 'Does the thickness of bass guitar strings affect how long the note plays' and I have to write a hypothesis &do backround information on it. Can anyone help me?

[Lyle Caldwell]

Well, it's a bit more complicated than that. There's a point of diminishing returns, because the greater the thickness, the greater the mass (assuming two strings of differing thickness but identical construction), so it takes more plucking force to energize the thicker string. Plus, in actual use, the greater the thickness, the greater the magnetic pull, hence less sustain.

And on a real bass, a thicker string requires a higher action, which means a greater behind the saddle angle, resulting in a very different tension on the heavier string.

So, experiment, but you'll have to lower the pickups about as low as they'll go and raise the action up high, even for the smaller strings, to begin to get a fair comparison.

And remember that differing methods of string construction can matter more than string thickness by itself.

[Finger Blister]

A bass string works both Newton's Laws and on Hooke's Law of Elastic Potential Energy.

Newton:
Greater Mass stores more energy.

Hooke:
Stretching stores energy.


A heavier gauge string, theorically requires more kinetic energy
to put into motion, and by virtue of it's mass, stores more
of this energy then a string with less mass.

Part of Newton's first law:
The more mass an object has the more inertia that object will possess.

Newton's second law:
The rate at which an object changes its velocity depends upon how much force is used and how much mass (inertia) the object has.

And then there's Elastic Potential Energy.

The amount of energy stored is amount of kinetic energy applied expressed as the force proportional to the distance the string is stretched. The more stretch, the more stored energy.

If stretched an equal amount -
the heavy gauge requires more work and stores more energy.

If equal 'attack' force is used -
the lighter gauge will stretch more...

Have we considered string tension yet???

[Rapidstatique]

Well I was thinking of the only variable was the string thickness. I know it can't be perfect, but as close as it'll get.

[nonsqtr]

You've chosen an exceedingly difficult experiment.

First off, how are you going to measure "how long the note plays"? My suggestion would be, rather than choosing an arbitrary metric, make a plot of the time course of the signal level after the string is plucked. The variation in the time course with different size strings should provide some useful information.

Then, your implication that string size can be changed by itself ("all other things being equal") is experimentally very difficult. String mass changes with string size, so how will you determine which part of the result belongs to the mass, and which part belongs to the size?

Then, if "all other things are equal", you'll need to come up with an experimental mechanism for plucking the strings with "equal force".

The hypothesis I would put forward (in the absence of additional information) is that "many factors" contribute to the sustain time of a plucked string, and I would seek to experimentally isolate "one" of those factors. I would also try to do the experiment "without" a pickup in place, since the interaction between the string and the magnet is extraordinarily complex and can't be easily analyzed with just a graph and few time series.

[tappel]

Check this out:

www.superstringtheory.com

Tom