What Does It Mean For A Force To Act On A Particle?

Click For Summary
SUMMARY

A force can act on a particle even if the particle does not move, as demonstrated by the example of a hydrogen atom in a magnetic field. The presence of an external force, such as a magnetic field, alters the equilibrium state and energy levels of the particle, indicating that the force is indeed acting on it. The discussion emphasizes that the work done by the force, represented by $$\vec{F} \cdot d\vec{s}$$, does not need to be non-zero for the force to be considered as acting on the particle. This understanding is crucial in fields such as quantum mechanics and classical mechanics.

PREREQUISITES
  • Understanding of classical mechanics principles
  • Familiarity with quantum mechanics concepts
  • Knowledge of potential wells and equilibrium states
  • Basic grasp of magnetic fields and their effects on atomic structures
NEXT STEPS
  • Explore the concept of potential wells in quantum mechanics
  • Study the effects of magnetic fields on atomic energy levels
  • Learn about the relationship between force and work in classical mechanics
  • Investigate equilibrium states and stability in physical systems
USEFUL FOR

Students and professionals in physics, particularly those studying mechanics and quantum mechanics, as well as educators looking to clarify the concept of force acting on particles.

iScience
Messages
466
Reaction score
5
I know this is kind of a dumb question but please forgive me it's been awhile.

Is it enough for a particle to merely "feel" an external force F to state that "F is acting on the particle"?
ie if the particle was confined in a potential well and experiences F but does not move.

or does $$\vec{F} \cdot d\vec{s}$$ have to be non-zero? ie does force have to do work on the particle to state that "F is acting on the particle"?
 
Physics news on Phys.org
Yes, I would say that a force 'acts' on a particle even if it doesn't move. It still affects the equilibrium state, meaning that the energy level, orbit, or whatever of the particle and its surrounding environment is different when the force is applied versus when it is not applied. Force example, if you place a hydrogen atom in a magnetic field the atomic energy levels shift slightly even though the electron is still in a stationary state and isn't being ripped from its atom and accelerated away.
 
  • Like
Likes   Reactions: Dale
Drakkith said:
Yes, I would say that a force 'acts' on a particle even if it doesn't move. It still affects the equilibrium state, meaning that the energy level, orbit, or whatever of the particle and its surrounding environment is different when the force is applied versus when it is not applied. Force example, if you place a hydrogen atom in a magnetic field the atomic energy levels shift slightly even though the electron is still in a stationary state and isn't being ripped from its atom and accelerated away.

Thank you!
 
Another simple example: hang a heavy body at the roof with an elastic thread; at equilibrium you can verify and measure the existence of the thread's force on the body with its elongation; cut the thread and the body falls down.

--
lightarrow
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
3
Views
1K
  • · Replies 12 ·
Replies
12
Views
2K
Replies
12
Views
2K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 14 ·
Replies
14
Views
4K
Replies
15
Views
2K
  • · Replies 13 ·
Replies
13
Views
2K