# 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. ### I Bead on a vertical frictionless ring

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3. ### A 4kg mass sits on a frictionless table....

I got 13N but is that right because apparently, it's wrong Here's my work: F = mg = 2(10) = 20N F = ma a = F/m = 20/4+2 = 20/6 = 10/3 = 3.3m/s^2 T = mg - ma T = (2kg)(10m/s^2) - (2kg)(3.3m/s^2) = 13.4 N I appreciate it! And if I'm wrong could you show how you got your answer? Thanks
4. ### Why are tension and friction in the same direction?

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5. ### Newton's laws--Block sliding up a frictionless semi-circular track

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6. ### B Will a round-headed rod topple if it slides down a frictionless slope?

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7. ### Preventing a block from sliding down a frictionless inclined plane

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8. ### Newton's laws — Two stacked blocks sliding on a frictionless floor

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10. ### I Changing the RPM of a frictionless spinning wheel in a box

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11. ### Can You Make a Frictionless Loop Turn?

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12. ### What happens when the maximum is exceeded in the Mass-Spring System?

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13. ### Vertical beam on a frictionless surface

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14. ### Two carts are held together, and when released they are pushed apart by a spring

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15. ### Influence of initial shift on undamped frictionless forced oscillations

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17. ### Oscillating Spring in a Frictionless pulley system

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19. ### Work of gravity on an object sliding down a frictionless sphere

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21. ### [Work check] Parametric frictionless wire

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22. ### Solving 8.62: Frictionless Stick in Morin's Classical Mechanics

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23. ### Object on a hemispherical hill

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24. ### How Does a Frictionless Ramp Affect Loot Crate Motion?

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25. ### Conceptual Question: Block on a wedge on a frictionless surface

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26. ### Solving Force and Motion: Pulling 25.0 kg Sled 25m

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29. ### Unnecessary Pump in a Frictionless Pipe: Impact on Pressure and Work

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30. ### How high does the frictionless ramp have to be for the ball....

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31. ### Angled falling Meter Stick on a frictionless surface

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32. ### Kinematics on a frictionless incline plane

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33. ### A frictionless incline with a block sliding down it....

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34. ### Will a sphere rotate on a frictionless inclined surface?

Well, my physics teacher taught us about rotation the other day and I came across a scenario where a sphere and a ring roll down a friction-less inclined plane from a point of absolute rest. I found it counter-intuitive as I started to think about why would they start rolling in the first place...
35. ### A question about rolling motion of a wheel on a frictionless surface

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36. ### Long rod rotating on frictionless surface

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37. ### Rotating mass on a frictionless table pulling up an object.

Homework Statement (General Physics - Algebra based) A 0.75 kg puck rotates in a horizontal circular motion on a frictionless table. It is attached to a string that is looped through a hole at the center of table and circular path. Attached to the other end of the string is a 1.5 kg block that...
38. M

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39. H

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40. O

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41. ### Acceleration of a frictionless block on a frictionless wedge

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42. ### Frictionless mass sliding in rotating pipe

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43. ### Motion on a frictionless Surface

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44. ### Frictionless ring sliding on circle in constant acceleration

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45. ### A rod at rest on ice is struck by a piece of clay....

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46. ### A mass is free to move on a horizontal frictionless surface

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47. ### A bead rests at the top of a fixed, frictionless hoop.

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48. ### Jumping off a moving cart on a frictionless track

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49. ### Mass sliding on frictionless inclined plane compresses a spring

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50. ### Friction Force on 2 blocks on a frictionless surface....

Homework Statement The two blocks ##(m=16 kg)## and ##(M=88 kg )## , are not attached to each other.The coefficient of static friction between the blocks is ##μ=0.33##, but the surface beneath the larger block is frictionless.What is the minimum magnitude of the horizontal...