# Science

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A weight lifter lifts a barbell from the ground, raises it at a constat velocity and holds it motionless over his head. How does the force of the lifter compare with the wieght of the barbell at different stages of the lift?

• Science -

w=F*d
d= 0m
0J....no work

• Science -

when the barbell is being lifted its weight is different than when it is stationary

• Science -

why don't you answer it yourself?

• Science -

A weight lifter lifts a 550 N weight 1.25 m over his head in 2.5 seconds. What is the power of the weight lifter?

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