1. The problem statement, all variables and given/known data a. Draw a free body diagram for mass Mb while in motion (fig. 2a). Identify the centripetal force. assume that the mass hangs vertically b. Calculate the magnitude of the force exerted by the spring on mass Mb = 402g, moving in a circle of radius r=18cm (fig. 2a). The mass makes 20 revolutions in 12 seconds. Determine the mass m, suspended over the pulley (fig 2b), which stretch the spring by the same amount as during the rotation. 2. Relevant equations 3. The attempt at a solution a. Mb would have 3 forces: F spring (Fsp), F centripetal force (Fc) and F gravity (Fg). Fsp is point outwards to the right, Fc pointing inwards to the left, and Fg is pointing downwards. I was wondering if it would have tension from the string supporting Mb? b. Fsp=Fc = mv2/r = m(2[tex]\pi[/tex]f)2r here, v = 2[tex]\pi[/tex]r/T = circumference/Period and frequency = 1/T 1) Fsp = 0.402kg x (2[tex]\pi[/tex] 20rev/12sec)2 x 0.18m' = 7.967 Nt I'm not entirely sure if what i did is correct. 2) I'm not entirely sure how to calculate m after this point.