14: A 1.15 kg mass oscillates according to the equation x=0.650cos(8.40t) where x is in meters and t in seconds. Determine (a) the amplitude, (b) the frequency, (c) the total energy, and (d) the kinetic energy and potential energy when x=0.360 m. Problem 20: An object with mass 2.7 kg is executing simple harmonic motion, attached to a spring with spring constant k=310 N/m. When the object is 0.020 m from its equilibrium position, it is moving with a speed of 0.55 m/s. (a) Calculate the amplitude of the motion. (b) Calculate the maximum speed attained by the object. Problem 22: Agent Arlene devised the following method of measuring the muzzle velocity of a rifle (see figure below). She fires a bullet into a 4.148 kg wooden block resting on a smooth surface, and attached to a spring of spring constant k=162.7 N/m. The bullet, whose mass is 7.870g, remains embedded in the wooden block. She measures the maximum distance that the block compresses the spring to be 9.460 cm. What is the speed v of the bullet