Hi there :) 1. The problem statement, all variables and given/known data I am currently preparing an experiment for IB physics, and I need some help planning how I'm going to carry it out. We were given the topic "Balls and Rubber Bands", and we could choose freely upon the exact research question. I personally chose "How does the increase of temperature affect the bounciness of squash balls". My teacher approved this topic. I currently plan to drop 5 different squash balls each time heated to the same, specific temperatures. After having dropped all five balls, I heat them up even more, and repeat the process. 2. Relevant equations None as of yet, I guess some basic maths calculations later on to find rebound height. 3. The attempt at a solution So, here are my questions: - What is the safest maximum temperature I should heat them up to without destroying the balls? My best guess was around 50 °C. - What is the best method to heat them up without damaging them? My best guess was to use a bunsen burner and heat it from the side. - How do I measure the rebound height without using a motion sensor, photoelectric gate, or a laser trigger (according to my teacher, the equipment we have at our school is inadequate)? My best guess was a 1 meter ruler, however I don't see how I would be able to accurately record the rebound height without using technology... Any help would be appreciated. Nothing is set in stone as of yet, so I can still change around the experiment if you guys think that it will be a good idea. If you guys don't think that such a research question will yield a good grade, please tell me so. I would prefer if you guys helped me work it out instead of giving a straight answer like other hw help sites do. Thanks!