Hello! First time posting here. I'm studying the IB and need to complete my required experimental write-up. I am looking to replicate the well-known experiment that finds the value of g by investigating the relationship between period and length of string for a simple pendulum. 1. The problem statement, all variables and given/known data I am required to put a "twist" on my experiment in order to surprise the examiner by my understanding of physics. I have an idea, but cannot find relevant information on the internet about whether it will work. 2. Relevant equations I will be using the length-period equation of a simple pendulum: T = 2pi sqrt(l/g). 3. The attempt at a solution My idea is to measure the period of the motion more accurately using digital means, rather than the traditional stopwatch. To my understanding this should provide me with a lower absolute uncertainty. I seek to measure the period by having a constant sound-producing source as the fixed mass on the pendulum and placing a microphone underneath the middle of the SHM (where the object's speed is greatest). I then want to somehow map the change in frequency (according to the Doppler effect) digitally and measure the time difference between each second maximum frequency to determine the period. I have a few questions: 1) What sort of software is available for this? 2) Is my experimental setup too dodgy? Will it impair the accuracy of my measurements? --- (My pendulum is two chairs and a broom between them as the experiment will be done at home) 3) Should I take the average of 10 periods, or just the first one? And why? 4) Any further comments on what I should do, and if this will even work will be appreciated. :) Thanks a lot!