Please provide rationale for 4 answers - thanks!
1) A student measures g, the acceleration due to gravity, five times, with the results (in m/s2): 9.92, 9.63, 9.54, 9.76, 9.82. What is the mean value of her measurements?
2) What is the uncertainty in her mean value?
3) What should she use as an estimate of the uncertainty of another measurement using the same procedures?
4) A torsion pendulum has a disk-shaped bob with a moment of inertia of 0.022 kg m2 hanging from a wire. The period of oscillation is 20 seconds. What is the torsion constant k of the wire in N m ?