# Question: a As a weightlifter lifts a barbell from the floor

(a) As a weightlifter lifts a barbell from the floor in the “clean” procedure (Fig. 5.25a), has he done work? Why or why not?

(b) In raising the barbell above his head in the “jerk” procedure, is he doing work? Explain.

(c) In holding the barbell above his head (Fig. 5.25b), is he doing more work, less work, or the same amount of work as in lifting the barbell? Explain.

(d) If the weightlifter drops the barbell, is work done on the bar-bell? Explain what happens in this situation.

(b) In raising the barbell above his head in the “jerk” procedure, is he doing work? Explain.

(c) In holding the barbell above his head (Fig. 5.25b), is he doing more work, less work, or the same amount of work as in lifting the barbell? Explain.

(d) If the weightlifter drops the barbell, is work done on the bar-bell? Explain what happens in this situation.

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