Problem 3: A mass is sliding on a frictionless surface with a speed v. It runs into a linear spring with a spring constant of k, which compresses from position x; to position .Xi xf . m m Otheexpertta.com Part (a) Write a general expression for the force that the spring exerts on the mass, in term of k and x. Choose the initial position of the front of the spring to be xi=0. Expression Fspring Select from the variables below to write your expression. Note that all variables may not be required. a, B, 0, a, d, g, h, j, k, m, P, t, X, Xf, Xi Part (b) Select the equation that correctly describes the work done by the spring to stop the mass. MultipleChoice : 1) W = -x. *f k x dx + 1/2mv2 2 ) W = - Jx. *f k x dx 3 ) W = - x *f k x dx - 1/2 mv2 4) W = - x. *fF x dx 5 ) W = -k x2 6) W = [x. *f k x dx Part (c) Evaluate the relationship in part (b) to arrive at an expression for the work done in terms of known variables. Expression : W = Select from the variables below to write your expression. Note that all variables may not be required. 0, p, 0, a, d, g, h, j, k, m, P, t, X, Xf, Xi Part (d) Solve for the numerical value of the work done in Joules given that x; = 0, xf= 38 cm, and k = 75 N/m. Numeric : A numeric value is expected and not an expression. W