During the laboratory exercise you plot a graph with acceleration, a, in ms-2,

along the y axis and the hangin? During the laboratory exercise you plot a graph with acceleration, a, in ms-2, along the y axis and the hanging mass, m, in grams, along the x axis. From this graph you record two gradients: da+/dm and da-/dm.

From the screen you read that for da+/dm:
Equation of line of best fit: y = 9.08 E-3 x -2.03 E-1
Equation of max gradient line: y = 1.05 E-2 x -2.79 E-1
Equation of min gradient line: y = 7.17 E-3 x -1.28 E-1
From the screen you read that for da-/dm:
Equation of line of best fit: y = 8.96 E-3 x -1.93 E-1
Equation of max gradient line: y = 9.91 E-3 x -1.81 E-1
Equation of min gradient line: y = 8.35 E-3 x -1.71 E-1

Use this data to answer the following questions. (0.05 can be entered as 0.05 OR as 5E-2).

a) What is the uncertainty in da+/dm? ...............ms-2g-1

b) What is the uncertainty in da-/dm? ..............ms-2g-1

c) Calculate da+/dm+da-/dm with an uncertainty. You may assume the uncertainties are dependent.

da+/dm+da-/dm = ( ± ) ...............ms-2g-1

d) 2g/M= da+/dm+da-/dm. Calculate M, the mass in kg, with an uncertainty given that g = 9.80 ms-2. (HINT: What unit is the gradient in? How do you convert it?)