Clarification

• Holding a stack of books--regardless of their weight--is really not work.blond holding batch of books image by Laser from Fotolia.com
  
  Work only occurs if there is a transfer of energy to an object, according to the article "Work." That means a student holding a stack of books is doing no work unless he or she is actually moving those books. Simply holding them in one spot is not work in the physics sense. Studying for a test is not work either because once again there is no movement of an object.
  
  

Determining the Amount of Work

• The formula to measure work is expressed as Work (W) = Force (F) x Distance (D). A newton is the unit used to measure force; it is defined as the force required to accelerate 1 kg of mass 1 m per second every second. To determine the number of newtons that have been applied to an object, multiply the mass of the object in kilograms by 9.8 m/sec2 which is the force of gravity. The result will be the force on the object expressed in newtons.
  
  

An Example

• A student carrying books to her desk performs work.girl with books image by jeecis from Fotolia.com
  
  If a student carries books from her locker to her desk, then work has occurred. To determine the amount of work performed, the student needs to find the distance between her locker and the desk. Let's say that distance is 25 m. If the books weigh 2 kg, then the force exerted on the books is 19.6 newtons (2 kg x 9.8 m/sec2 which is the force of gravity). By multiplying the force of 19.6 newtons by the distance of 25 m, then the amount of work is equal to 490 newton-meters. Since one newton-meter is equal to one joule, then 490 joules of work has occurred.
  
  

Other Considerations

• There are times when only part of a force moves an object; for example, in carrying books to class, a person may be exerting a force on the books with her arms to hold them. However, since the books are being carried to a desk, only the force applied in the direction of the desk would represent work; although the arms are keeping the books from falling to the floor, the direction (and thus the force) is toward the desk.
  
  

A Summary

• Studying isn't work according to the scientific definition.girl the heap of books image by Serg Zastavkin from Fotolia.com
  
  While people may refer to a variety of everyday actions as work, it is only those actions that actually cause an object to move through a distance in the same direction that the force is applied that are truly work. If there is no movement of the object or the object does not move in the direction of the applied force, then no work has occurred regardless of the effort exerted.