1. The problem statement, all variables and given/known data Three masses (m1 = 4.4 kg, m2 = 13.2 kg and m3 = 8.8) hang from three identical springs in a motionless elevator. The springs all have the same spring constant, which is 268 N/m. The elevator is moving downward with a velocity of v = -3.7 m/s but accelerating downward at an acceleration of a = -1.6 m/s2 (speeding up). What is the magnitude of the net force on the middle mass? 2. Relevant equations F = -kx Net Force = m(a - g) 3. The attempt at a solution I drew a free body diagram and found out the forces acting upon the middle mass. However, I don't think this is the way to go, since what I did was calculate those forces and then subtract one from the other.