Trivial question about friction

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SUMMARY

The discussion centers on calculating the motion of an object subjected to a force of 384.16N and a mass of 98kg, with dynamic friction acting on it. The normal force is established at 960N, with a static friction coefficient of 0.4 and a dynamic friction coefficient of 0.14. The initial acceleration calculated is 3.92m/s², and the user seeks to determine the time required for the object to travel 10 meters, concluding that the initial acceleration should be considered in the calculations. The key takeaway is the necessity of applying kinematics formulas to solve the problem effectively.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Knowledge of kinematics equations
  • Familiarity with friction coefficients (static and dynamic)
  • Basic algebra for solving equations
NEXT STEPS
  • Study the application of Newton's second law in dynamic systems
  • Learn how to apply kinematics equations for uniformly accelerated motion
  • Explore the differences between static and dynamic friction in practical scenarios
  • Investigate the effects of varying mass and force on acceleration and distance
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Students in physics, engineers dealing with mechanics, and anyone interested in understanding motion under frictional forces will benefit from this discussion.

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Homework Statement


I have this doubt, I think its trivial, but I don't know how to express this thing mathematically. The thing is, I have a force F applied to an object of mas m over an horizontal path, under the action of a dynamic friction force. I know that with the force F the object will suffer an acceleration a. Let's suppose the force is F=384.16N, the mass is 98kg, the normal force is 98kg.g=960N, and the static friction coefficient is 0.4 and dynamic friction coefficient is 0.14. The object is over an horizontal surface, so the normal force is equal to the weight. The acceleration that the object will suffer due to the force is 3.92m/s^2. But the force that produces that acceleration its applied just once, so then the acceleration decays due to the dynamic friction. So I want to know how long it will take to the object to travel a distance of 10 meters. How should I proceed? should I consider an initial acceleration? how do I express the action of the dynamic friction at every instant of time?

Bye, and thanks for posting.
 
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You use static friction to figure out if the object accelerates at all. If it doesn't, then dynamic friction is completely meaningless. If it does, then you use dynamic friction to figure out how much it accelerates. From there, you simply use those good old kinematics formulas.
 
Thanks Planck. I have just realized what I have to do. I just must consider the acceleration given by the force as an initial acceleration.

Bye there!
 

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