5. A weightlifter lifts a barbell of mass 50 kg to a height of 2m in 3s. (Take g = 9.8 m/s².) a) What is the weight of the barbell? 5. A weightlifter lifts a barbell of mass 50 kg to a height of 2m in 3s . ( Take g = 9.8 m / s² . ) a ) What is the weight of the barbell ?
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