1. The problem statement, all variables and given/known data What is the effective spring constant for the system of the two springs, perfect pulley, and string shown on the left for it to be modeled by just one spring (constant keff) as shown on the right? Use only the variables k1 and k2 in your answer. 3. The attempt at a solution I know that the springs in parallel get added because they undergo same change in distance and springs in series have the same effective constant as resistors in parallel .They experience equal forces. I don't understand that will happen in the given sitch ,will the lower spring (2) stretch? will the upper spring stretch too?(because we are pulling down) how will I write the equations? I know that the force experienced by both is equal.