1. The problem statement, all variables and given/known data for problem 1 A 2.50 kg object placed on a frictionless, horizontal table is connected to a string that passes over a pulley and then is fastened to a hanging 9.00 kg object, as shown in the figure. Find the magnitude of the acceleration of the two objects and the tension in the string. 2. Relevant equations for problem 1 F=ma 3. The attempt at a solution for problem 1 I have absolutely no idea how to go about solving this. Originally, I was thinking that the acceleration would simply be gravity, since the table is frictionless and there is no friction acting on the block sitting on the table to inhibit the downward motion of the hanging block. Obviously, that is wrong. 1. The problem statement, all variables and given/known data for problem 2 A 2.60 kg object is moving in a plane, with its x and y coordinates given by x = 4t2 - 1 and y = 4t3 + 4, where x and y are in meters and t is in seconds. Find the magnitude of the net force acting on this object at t = 2.45 s. 2. Relevant equations for problem 2 F=ma 3. The attempt at a solution for problem 2 I originally took the first derivative of each component equation, inserted the given value for t, and then did the following to obtain a resulting number from both components: a = sqrt(x^2+y^2). Obviously I am quite lost. Am I on the right track by using derivatives? Should I be putting the y equation over the x equation (rise over run, slope) and taking the first derivative of that?