Does 200 Foot-Pounds of Work Require More Work?

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SUMMARY

The discussion clarifies that lifting a 50 lb weight over a distance of 4 feet results in 200 foot-pounds of work. However, when holding the weight and walking horizontally for an additional 4 feet, no extra work is required. This conclusion is based on the principle that work is defined as the dot product of force and displacement, which equals zero when the force is perpendicular to the direction of motion.

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jonathan.15
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You lift a 50 lb weight by a distance of 4 ft so you do 200 foot-pounds of work. You then hold the weight and walk a horizontal distance of 4 feet, does this require an additional 200 foot-pounds of work? Please excuse the units, this question came from a calculus book.
 
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The simple answer would be ; no. This is because the force your hand applies perpendicular to the direction of motion of the weight. The definition of work involves a dot product, which is zero for 2 perpendicular vectors.
 

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