# physics

posted by kalisha

A weightlifter holding a 500 kg barbell waist high carries the barbell at a constant height and a constant speed to a rack 2 m away, and places the barbell on the rack at the same height at which he was carrying it. How much work does the weightlifter do on the barbell?

1. bobpursley

Constant height? He did not work against gravity, then.

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