1. The problem statement, all variables and given/known data You are in a space ship far from any other objects, and you want to build a clock. You decide to build your clock out of a spring with a mass attached to it. You use a spring with spring constant k = 138 N/m, and you initially displace the mass a distance x=25.0 cm from equilibrium. a) How much mass will you need so that your clock will measure seconds? b) What is the max velocity of the attached mass? c) Draw a plot of the spring potential energy (Usp) as a function of time for two periods of the clock. The plot must be neat and include numeric values for the max Usp. Make sure you also label the points when Usp is a min and a max, Give the numeric values for both the time and Usp. 2. Relevant equations T= 2π ⋅ √m/k V(max) = ± A ⋅ √k/m 3. The attempt at a solution a) T2/ 4π2= m/k m=(k * T^2)/(4 * π2) m= 138 * 1 sec / ( 4 * π^2) m= 3.50 kg (is this correct?) b) V (max) = ± 0.25 m * √(138 N/m /3.496 kg) = ± 1.57 m/s (is this correct?) c) I don't understand this part.