1.The problem statement, all variables and given/known data Two masses hang from a string running over a pulley. Such a device can be used to measure the acceleration of gravity; it is then called Atwood's machine. If the masses are nearly equal, then the a of the masses will be much smaller than g; than makes it convienient to measure a and then calculate g. Suppose than an experimenter using masses m1= 450g and m2=452g finds that the masses move a distance of 0.472m in 5.8s starting from rest. What value of g does this imply? Assume the pulley is massless. 2. Relevant equations I know that a=(m2-m1/(m2+m1))g 3. The attempt at a solution From the above equation, I know that a=0.0022g When using a=2y/t2, though I get g=12.8m/s/s, which is wrong (online hw). Can anyone point me in the right direction?