Task 29: Work, power and the conservation of energy Objective: Demonstrating the use of the work-energy theorem as an alternative to using kinematics equations, and how the concept of power is used. 1. A 20.0 N tension force that is pointed at 25.0 from the right is applied to a 3.00 kg box that is travelling to the left on the floor. The floor's coefficient of kinetic friction is 0.100. a. Draw a picture of the situation; this does not have to be a free- body diagram. Include a coordinate system. b. How much work is done by the tension force when the box has moved 12.0 m to the left? Is it positive or negative? Draw a vector diagram to illustrate how you are finding the value. c. Fill in the blanks with "increases", "decreases" or "stays the same": The kinetic energy of the box as it moves along the floor; its gravitational potential energy The thermal energy of the floor which explains where the "missing" energy went. d. Using the work-energy equation, solve for the final velocity of the box after 12.0 m of motion. The initial velocity of the box is 15.0 m/s. e. Draw a free-body diagram for this scenario. Remember to label ALL forces, and to include a coordinate system. f. What is the final velocity of the box after 12.0 m of motion? Do NOT use the work-energy equation; use Newton's First and Second Laws, as we did in prior chapters, to solve for the box's acceleration, then use kinematics equations to determine the final velocity. You may assume the initial velocity of the box is 15.0 m/s