Work, Vertical and Horizontally

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The discussion focuses on calculating the work done by a person lifting a 3.7 kg cement block vertically and then carrying it horizontally. The work done in lifting the block can be calculated using the formula w = fd, where f is the force (weight of the block) and d is the distance lifted. In contrast, the work done while carrying the block horizontally is zero, as there is no vertical displacement. Gravity does negative work during the lifting process, equal to the weight of the block multiplied by the distance lifted. Understanding these principles is essential for solving similar physics problems.
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A person lifts a 3.7 kg cement block a vertical distance of 1.18 m and then carries the block horizontally a distance of 7.80 m.

(a) How much work is done by the person in the process?
J

(b) How much work is done by gravity in the process?
J

w=fd?
 
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Bigdane said:
A person lifts a 3.7 kg cement block a vertical distance of 1.18 m and then carries the block horizontally a distance of 7.80 m.

(a) How much work is done by the person in the process?
J

(b) How much work is done by gravity in the process?
J

w=fd?

OK. How much work then in lifting?

How much in carrying?
 
im not sure how to find that
 
got it. thanks
 

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