ok so, my coursework is to measure the oscillations of a mass on a beam to prove that T^2 = k l^3 when k is a constant of proportionality. And basically when plotting the graph of my results, the first 8 results fit exactly on my line of best fit but the last two are completely off. These results where at the longest lengths of the beam. Would this affect the time period in any way? Would it be because there is a greater mass as there is more of the beam oscillating? Please help!