Can Negative Force Result in Positive Work?

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SUMMARY

The discussion centers on the concept of work in physics, specifically addressing whether negative force can result in positive work. It is established that work is defined as the dot product of force and displacement. If both force and displacement are in the same direction, even if that direction is negative, the work done is positive. This is due to the mathematical relationship where the angle between force and displacement is less than 90 degrees, leading to a positive product.

PREREQUISITES
  • Understanding of basic physics concepts, particularly force and displacement.
  • Familiarity with the dot product in vector mathematics.
  • Knowledge of the relationship between angles and work calculations.
  • Basic grasp of positive and negative values in mathematical contexts.
NEXT STEPS
  • Study the principles of vector mathematics, focusing on the dot product.
  • Explore the concept of work-energy theorem in physics.
  • Investigate scenarios involving force and displacement in different quadrants.
  • Learn about the implications of negative work in physical systems.
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Students of physics, educators teaching mechanics, and anyone interested in understanding the nuances of work and energy in physical systems.

zhao
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Is there an example where you are pushing in the negative direction (force in negative direction) and yet doing positive work?

please help me
 
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What is the definition of "WORK"?
 
If you are pushing in the negative direction, and force is in the negative direction, the work done is always positive.

Work is the dot product of force and displacement. Thus if the angle between the displacement and force is less than 90 degrees, the work will always be positive.
 
Please try to give the OP a chance to answer.
 
Sorry, your post was not up as I was typing my response.
 
well, work is equal to Force * Displacement

I was thinking if displacement and force are both negative, it will give a pos. work
 

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