Hello all, I am currently working at a problem that is (seems) simple at calculations but I am puzzled by the word problems. The problems are: 1. A spring powered projectile launcher contains a spring with: k=300 N/m The spring is compressed by 15.0 cm. a. How much energy is stored in the compressed spring? My answer is: 1/2 kx^2, and the answer is about 3.375J b. How fast would a 38 g projectile be traveling if it were shot by this projectile launcher? my answer is 13.3278 m/s So my question is: would using a lighter projectile provide more momentum or less? Prove the statement algebraically. Second question is: a truck sinks lower when you load it and it bounces slowly when it is loaded than when it is empty. Explain these phenomena using formulas.