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Zorluk: OrtaFriction and Resistance

A heavy steel block must be moved along a level track. Rank the following methods or conditions based on the amount of frictional resistance they generate, from LEAST resistance to GREATEST resistance.

  1. 1Floating the block on a highly pressurized film of oil
  2. 2Moving the block on cylindrical steel rollers
  3. 3Sliding the block continuously along the dry track
  4. 4Pushing the stationary block until it just breaks free

Cevap

The correct order from least to greatest resistance is: floating on oil (fluid friction), moving on rollers (rolling friction), sliding continuously (kinetic friction), and overcoming the initial standstill (static friction).
Fluid friction separates the surfaces entirely, offering the least resistance. Rolling friction prevents surfaces from dragging, making it the second lowest. For the dry track, sliding (kinetic) friction is less than the static friction required to break the object's initial grip, making static friction the greatest resistance.

Adım Adım Çözüm

1
Identify the primary type of friction acting in each scenario.
Oil film involves fluid friction; steel rollers involve rolling friction; continuous sliding involves kinetic friction; breaking free from a standstill involves static friction.
Categorizing the physical interaction is required to compare their relative magnitudes.
2
Determine the lowest sources of friction.
Fluid friction creates the least resistance, followed closely by rolling friction.
Fluids deform easily to allow movement and separate the surfaces entirely, while rollers prevent direct surface scraping.
3
Compare the resistance of a moving object versus a stationary object on the exact same dry surface.
Kinetic (sliding) friction is always less than the maximum static (standstill) friction.
Once the microscopic bonds between the resting surfaces are broken, it takes less force to keep the object moving than it did to start it.
4
Arrange the scenarios from least to greatest based on these physical principles.
The correct sequence is: Fluid, Rolling, Kinetic, Static.
This correctly orders the magnitudes of frictional resistance from lowest to highest.

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Friction and Resistance
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Friction and Resistance

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