Acceleration across a frictionless surface

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When an object is pushed on a frictionless surface, it accelerates according to Newton's second law (F=ma). Once the applied force is removed, the object stops accelerating and continues at a constant velocity, as per Newton's first law. For example, pushing a 100kg object with 200N for 2 seconds results in a final velocity of 4m/s. This velocity remains constant indefinitely on a frictionless surface after the force is no longer applied. The discussion clarifies the relationship between force, mass, acceleration, and motion in the absence of friction.
Sammy101
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Hi, I am confused on the topic of friction. I thought of a question that I cannot answer.

What happens if you push an object with a certain amount of force and mass on a frictionless surface? According to F=ma, you will be able to get the acceleration of the object, but how will you know when the object stops acceleration? Will the object accelerate infinitely?
 
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As soon as you stop applying force to the object it will cease accelerating. IE if you push a block, as soon as you take your hand off or stop pushing it will cease accelerating.
 
And so then it will just continue at a constant velocity right?

So, if you pushed on a 100kg object with 200N of force for 2s and then let go on a frictionless surface, the objects final velocity would be 4m/s because:

F=ma
200N=100kg(a)
a=2m/s^2

t=2s
velocity= 2m/s^2(2s) = 4m/s and that's how fast it would travel forever on a frictionless surface?
 
Yes, as soon as the force applied ceases, the object will continue at whatever velocity it was when you removed the force.
 
Thank you!
 
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