Hi, I am doing my Extended Essay in Physics(so yeah, I am doing the IB). I am really interested in taking up electrical engineering at university, and so, I had done an EE in piezoelectricity. I have taken the crystal from a barbecue lighter and connected it to a vernier( a machine that can read potential differences and transfer it to a computer). So, to investigate the effects of input force on output voltage, I have dropped masses onto a stick pressing onto the crystal using a pulley from known heights( so that I know the value of the impulse) and then recorded the voltages generated as a function of time. I am just very worried about whether I am interpreting my data properly. I am planning to calculate the average of the highest peaks in each graph(but only in the positive, as I feel that the stick pressing down on the crystal may have affected the voltage in the negative region. Then, I intend to compare these values. Is this correct? Does anyone have any suggestions? Am I doing anything anything scientifically wrong? Also I have noticed that at the beginning of each graph, there is one period of the function(which is not as high as the next one, which is almost always the highest), which I am finding hard to explain. Any ideas here? Thanks in advance for helping me.