PHYSICS · Subjective · Fermi University Physics · Scientific Practice & Experimental Methods · Uncertainty in measurement · Data analysis and model fitting in the laboratory
Measurement and Method, Ch Graphs, straight lines and least squares
Problem
A mass M hung on a spring oscillates with period T=2π(M+ms)/k, where k is the spring constant and ms is an effective mass contributed by the spring itself. The period is timed for six hanging masses, each period with standard uncertainty u(T)=0.004s. Choose the quantity to plot on each axis so that the relation becomes a straight line Y=mX+c0, and state what the slope and the intercept each measure. The least-squares line through the six points has slope m=3.95s2kg−1 and intercept c0=0.079s2. Find k and ms. One point has T=(0.800±0.004)s. What value, and what vertical error bar, does it carry on your plot?