If Kinetic friction is a constant can I accelerate forever?

AI Thread Summary
Kinetic friction is constant at 5 N, but the limiting friction of 10 N means that once the object is in motion, the applied force must exceed this to maintain acceleration. If a continuous force of 20 N is applied, the net force acting on the object will be 10 N, leading to acceleration. Reducing the applied force to 6 N results in a net force of 1 N, allowing for continued acceleration, albeit at a slower rate. The discussion highlights the relationship between force, friction, and the resulting heat generated from motion. Ultimately, understanding these dynamics is crucial for analyzing motion and energy in physics.
sameeralord
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If a limiting friction of an object is 10N and the kinetic friction is 5 N.

If I apply a force of 20 N continuosly would I be accelerating with a 5 N force forever.
 
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sameeralord said:
If a limiting friction of an object is 10N and the kinetic friction is 5 N.

If I apply a force of 20 N continuosly would I be accelerating with a 5 N force forever.

Hi sameeralord! :smile:

(limiting friction is the maximum value of static friction)

No … you would be accelerating with a 10 N force forever …

once the object has started moving, you can forget the static friction completely (and you can reduce the applied force).

So if you apply a force of 6 N continuously, you will be accelerating with a 1 N force forever. :wink:​
 
tiny-tim said:
you would be accelerating with a 10 N force forever
You meant 15 N. Right?
 
DaleSpam said:
You meant 15 N. Right?

Right! :smile:
 
You do need more and more power to overcome friction. The heat produced will become a problem too.
 
Now this is a "work" problem. Are you familiar with "work"?

Work is a measurement of energy, and is equal to force X distance.

In this case, 15N (the force of friction) times the distance the object slides = the heat energy given off (in "joules").

So, when the object is moving faster, it covers more distance per unit time, so it also generates more heat per unit time.
 

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