What is Frictionless: Definition and 475 Discussions

The frictionless plane is a concept from the writings of Galileo Galilei. In his 1608 The Two New Sciences, Galileo presented a formula that predicted the motion of an object moving down an inclined plane. His formula was based upon his past experimentation with free-falling bodies. However, his model was not based upon experimentation with objects moving down an inclined plane, but from his conceptual modeling of the forces acting upon the object. Galileo understood the mechanics of the inclined plane as the combination of horizontal and vertical vectors; the result of gravity acting upon the object, diverted by the slope of the plane.However, Galileo's equations do not contemplate friction, and therefore do not perfectly predict the results of an actual experiment. This is because some energy is always lost when one mass applies a non-zero normal force to another. Therefore, the observed speed, acceleration and distance traveled should be less than Galileo predicts. This energy is lost in forms like sound and heat. However, from Galileo's predictions of an object moving down an inclined plane in a frictionless environment, he created the theoretical foundation for extremely fruitful real-world experimental prediction.Frictionless planes do not exist in the real world. However, if they did, one can be almost certain that objects on them would behave exactly as Galileo predicts. Despite their nonexistence, they have considerable value in the design of engines, motors, roadways, and even tow-truck beds, to name a few examples.The effect of friction on an object moving down an inclined plane can be calculated as





F


f



=

μ


k




F


N



,


{\displaystyle F_{\mathrm {f} }=\mu _{\mathrm {k} }F_{\mathrm {N} },}
where




F


f





{\displaystyle F_{\mathrm {f} }}
is the force of friction exerted by the object and the inclined plane on each other, parallel to the surface of the plane,




F


N





{\displaystyle F_{\mathrm {N} }}
is the normal force exerted by the object and the plane on each other, directed perpendicular to the plane, and




μ


k





{\displaystyle \mu _{\mathrm {k} }}
is the coefficient of kinetic friction.Unless the inclined plane is in a vacuum, a (usually) small amount of potential energy is also lost to air drag.

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  1. D

    Frictionless body on Earth's Surface

    Homework Statement Will a frictionless body placed on the Earth move, and if so, describe it's path and acceleration. Homework Equations I was given no equations, but I believe that coriolis and centripetal forces would act on the body.The Attempt at a Solution I assume that we have to assume...
  2. Kernul

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  3. Const@ntine

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  4. Turhan

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  5. L

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  6. L

    Conservation of Energy on a frictionless incline

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  7. BrainMan

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  8. Mr Davis 97

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  9. Mr Davis 97

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    Homework Statement This problem involves solving a simple differential equation. A block of mass ##m## slides on a frictionless table. It is constrained to move inside a ring of radius ##l## that is fixed to the table. At t = 0, the block is moving along the inside of the ring (in the...
  10. Erenjaeger

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  11. Mohamed_Wael

    Stiffness Matrix of Frictionless Plate Support: Puzzling Differences

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  12. L

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  13. S

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  14. D

    Dynamics of Rotational Motion and hinge

    One end of a thin, uniform rod is connected to a frictionless hinge as shown in Figure 1. The rod has a length of 0.8 mand a mass of 2 kg. It is held up in the horizontal position (θ=90∘) and then released. 1)Calculate the angular velocity of the rod at θ=90∘. 2)Calculate the angular...
  15. Anjum S Khan

    Velocity along a frictionless surface

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  16. P

    Two blocks on a frictionless surface; find the force

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  17. P

    Rope falling through a hole on a frictionless table

    Homework Statement A rope with uniform density ##\lambda=\frac{m}{L}## is placed on a frictionless table with an initial length ##y_0## hanging through the hole. Derive a differential equation for the position of the bottom of the rope and then using this solve for the time required for the...
  18. Eclair_de_XII

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  19. I

    Can a car drive around a frictionless mountain?

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  20. henrco

    Calculate total mechanical energy of a frictionless spring

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  21. T

    Can't understand 2 pulley 3 masses problem

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  22. 5P@N

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  23. B

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  24. C

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  25. komarxian

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  26. komarxian

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  27. R

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  28. V

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  29. Nathanael

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  30. WhiteG7

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  31. 1350-F

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  32. K

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  33. Thornak

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  34. J

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  35. B

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  36. S

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  37. N

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  38. T

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  39. D

    Initial acceleration problem: Two children on a frictionless floor

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  40. SpacemanRich

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  41. J

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  42. A

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  43. Y

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  44. D

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  45. Cake

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  46. P

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  47. L

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  48. J

    Collision of 2 balls on frictionless surface

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  49. R

    Horizontal velocity over an uneven surface

    Homework Statement A small ball of m=1kg at height hp = 8m at point p, is given an initial horizontal speed vp = 10 m/s. It slides over an uneven frictionless surface. What is speed vq of the ball at height hq = 3m at point q? Homework Equations Ui + KEi = Uf + KEf The Attempt at a Solution...
  50. S

    Frictionless Situations - How to get Velocity -Time information

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