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WHITE BOARD TIME !! Work Changes KE A 4 kg bowling ball is rolling down the hallway with an initial speed of 2 m/s. Gaby exerts a constant force through a displacement of 0.4 m. The force exerted by Gaby does -0.6 J of work (assume no force of friction). What’s the final velocity of the ball? 1.List all physical quantities. m= F= m= vi = Dd = vF = KEi = W= KEF = 2.Write the work-energy theorem relationship. Solve for velocity. 3.Make a bar chart of KEi + W = KEF A 0.05 kg bullet traveling at 200 m/s hits a post 0.5 m thick. The bullet comes out on the other side of the post with a speed of 120 m/s. 1.List all physical quantities. m= F= m= vi = Dd = vF = KEi = W= KEF = 2.Write the work-energy theorem relationship. Solve for the force exerted by the post on the bullet. 3.Make a bar chart of KEi + W = KEF Holly exerts a constant force of 12 N at 60º above the horizontal on a 6.4 kg sled. Assume the sled starts at 0.5 m/s and slides horizontally through a displacement of 2 m. (assume no force of friction). 1.List all physical quantities. m= F= m= vi = Dd = vF = KEi = W= KEF = 2.Write the work-energy theorem relationship. Solve for the force exerted by the post on the bullet. 3.Make a bar chart of KEi + W = KEF