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. L

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    can anyone help me to solve this question? please and thank you :D A small block slides from rest from the top of a fixed frictionless sphere of radius R. Determine the vertical distance traveled by the block, x , where it loses contact with the...
  2. L

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  3. M

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  4. P

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    1. Under all ordinary conditions, would a ball released from rest start rolling down a frictionless inclined plane with just the force of gravity pulling it down? Or is it really just going to slide down? Now let's suppose a gigantic ball released on the slope of an enormous frictionless...
  5. A

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  6. S

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  7. R

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  8. B

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  9. E

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  10. C

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  11. G

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  12. L

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    Homework Statement A shipping container is hauled up a roller ramp that is effectively frictionless at a constant speed of 2.10 m/s by a 2250 N force that is parallel to the ramp. If the ramp is at a 24.7° incline, what is the container's mass? Homework Equations Fx = mg sin(theta) F =...
  13. L

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  14. S

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  15. J

    Drag of Car across frictionless surface.

    1. a 1400 kg car with a cross section of 1.8m wide and 1.46m high slides across a frictionless surface at 19 m/s. The question is how long does it take (in seconds) to get to 13 m/s? the 2nd part is how long it does it take to get to 10 m/s? 2. D = .5(A)v^2 where A is the area of cross...
  16. S

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    There are actually 2 questions that i have Homework Statement First is a frictionless pulley with zero mass is attached to the ceiling, in a gravity field of 9.80 m/s2. Mass M2=0.250 kg is being accelerated downward with a=1.40m/s2. calculate the mass m1. Second is A small steel ball...
  17. P

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  18. S

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  19. P

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  20. S

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  21. S

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  22. R

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  23. B

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  24. D

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  25. S

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  26. B

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  27. A

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  28. V

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  29. S

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  30. J

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  31. S

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  32. P

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    I'm stuck on this problem. A sledge of mass 120 kg is at rest on a horizontal icy surface. A man of mass 70 kg stands at one end of the sledge so the initially the distance from the man to the shore is 20 m. The man now walks 3 m relative to the sledge, towards the shore. The he stops...
  33. E

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  34. B

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  35. nickclarson

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  36. L

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  37. nickclarson

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  38. P

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  39. W

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  40. M

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  41. D

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  42. S

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  43. O

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  44. R

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  45. F

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  46. M

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  47. S

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  48. P

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  49. T

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  50. K

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