A weightlifter holds a 1,500 N barbell 1 meter above the ground. One end of a 2-meter-long chain hangs from the center of the barbell. The chain has a total weight of 200 N. How much work (in J) is required to lift the barbell to a height of 2 m?
What is the average force (in N) (average with respect to height of the barbell from the ground) exerted by the weightlifter in the process?