### sachy

Posted 23 April 2006 - 04:31 PM

could someone please send me some information on determing the value of gravity using a spiral spring. I need this urgently ....the deadline for my project is tomorrow. If anyone has anything relevant please post!!!

### Dave

Posted 23 April 2006 - 08:53 PM

talk about leaving it late. I dont have anything on my however, sorry.

however, if you google the experiment you will no doubt find a number of university pages outlining what is done and why etc

### dfx

Posted 23 April 2006 - 10:09 PM

A mass suspended on a spring when pulled and released will oscillate in simple harmonic motion. If we consider the forces acting on a mass hung on a spring we have:

weight of the mass = restoring force of the spring (so the system is in equilibrium)

thus mg = kx

then k/m = g/x

Then in simple harmonic motion T = 2pi x sq.rt. (m/k)

substituting m/k for x/g into the Time period equation. you now have an equation with x and g in it. Square both sides to get

T^2 = (4pi^2)x/g then set several extension for the spring x and let the system oscillate, measure the Time period T for each oscillation, find T^2 and plot against x the extension. From the graph the gradient equals 4pi^2 /g then solve for g.

### Vixus

Posted 29 April 2006 - 02:37 PM

You mean you did your entire project in an afternoon?