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How much work?

  1. Jun 17, 2013 #1
    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.
     
  2. jcsd
  3. Jun 18, 2013 #2
    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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