What is Normal force: Definition and 470 Discussions

In mechanics, the normal force




F

n





{\displaystyle F_{n}\ }
is the component of a contact force that is perpendicular to the surface that an object contacts, as in Figure 1. In this instance normal is used in the geometric sense and means perpendicular, as opposed to the common language use of normal meaning "ordinary" or "expected". A person standing still on a platform is acted upon by gravity, which would pull them down towards the Earth's core unless there were a countervailing force from the resistance of the platform's molecules, a force which is named the "normal force".
The normal force is one type of ground reaction force. If the person stands on a slope and does not sink into the ground or slide downhill, the total ground reaction force can be divided into two components: a normal force perpendicular to the ground and a frictional force parallel to the ground. In another common situation, if an object hits a surface with some speed, and the surface can withstand the impact, the normal force provides for a rapid deceleration, which will depend on the flexibility of the surface and the object.

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  1. SirMarx01

    Automotive What is the compression force of a ring seated inside a cylinder

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  2. Beth N

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  3. W

    My Second Post: Change in Magnitude of Normal Force?

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  4. U

    B Where's the action force if the normal force is a reaction force?

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  5. SmamMir

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  6. isukatphysics69

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  7. J

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  8. Liam C

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  9. Johns24

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  10. N

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  11. E

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  12. M

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  13. E

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  15. N

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  16. M

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  17. R

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  18. M

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  19. L

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  21. B

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  22. IntegralBeing

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  23. A

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  25. F

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  27. T

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  28. E

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  31. P

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  32. J

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  33. Shardul Khare

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  34. W

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  35. Shardul Khare

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  36. Hallucinogen

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  37. G

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  38. Likith D

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  39. B

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  40. A

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  41. OrlandoLewis

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  42. M

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  43. A

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  44. D

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  45. Surya97

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  46. G

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  47. RoboNerd

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  48. E

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  49. John Pang

    I Why is normal force always perpendicular to the surface?

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  50. J

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