A force does work on an object when it causes a displacement of the object.

Why "Displacement"?

In physics, work requires both force and motion in the direction of that force. Displacement is the key change in position; without it, no work occursā€”even if force is applied. For example, pushing a wall does nothing since there's no movement.

The formula confirms this: W=Fdcosā”ĪøW=Fd\cos \theta W=FdcosĪø, where ddd is displacement.

Quick Examples

  • Lifting a book: Force upward causes upward displacement ā†’ work done.
  • Pulling a wagon: Horizontal force matches horizontal movement ā†’ work done.
  • Holding a heavy bag still: Force applied, but no displacement ā†’ no work.

Common Misconceptions

  • Every force does work? Noā€”perpendicular forces (like gravity on horizontal motion) yield zero work since cosā”90āˆ˜=0\cos 90^\circ =0cos90āˆ˜=0.
  • Everyday vs. physics "work": In daily talk, "work" means effort; physics demands displacement.

TL;DR: The word is displacement.

Information gathered from public forums or data available on the internet and portrayed here.