A weightlifter holds a 1,700 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 800 N. How much work (in J) is required to lift the barbell to a height of 2 m

W = 5000 J

Explanation:

Weight hold by a weightlifter is 1700 N, 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 800 N.

We need to find the work is required to lift the barbell to a height of 2 m.

Total force is : 1700 N + 800 N = 2500 N

Work done in Physics is given by :

W = F×d

So,

W = 2500 N × 2 m

W = 5000 J

Hence, 5000 J of work is required to lift the barbell to a height of 2 m.

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