Newton's law of motion -- crates & strings & friction

AI Thread Summary
To solve the problem of three boxes connected by strings at a constant speed of 2.0 m/s, it's essential to understand that acceleration (a) is zero, meaning the net force is also zero. Despite this, forces such as friction still exist and can be calculated using the coefficient of static and kinetic friction. A free body diagram (FBD) for each crate should be drawn to visualize the forces acting on them, including frictional forces. The equation F = ma indicates that if acceleration is zero, the forces acting on the system must balance out. Understanding these concepts is crucial for determining the forces involved in the scenario.
HTT
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Homework Statement


three boxes connected by strings.
given the mass of each box, coefficient of static and kinetic friction, and a constant speed of 2.0 m/s

I want to know how to get force by a given speed...!
Also, at a constant speed, how do I get to know the acceleration? does a = 0? if a = 0, how can I find Forces?

Homework Equations



F = ma

The Attempt at a Solution

 
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HTT said:

Homework Statement


three boxes connected by strings.
given the mass of each box, coefficient of static and kinetic friction, and a constant speed of 2.0 m/s

I want to know how to get force by a given speed...!
Also, at a constant speed, how do I get to know the acceleration? does a = 0? if a = 0, how can I find Forces?

Homework Equations



F = ma

The Attempt at a Solution


Start this kind of problem by drawing a free body diagram (FBD) of each of the crates. Be sure to show the frictional forces... that is how you can have a force even when the net acceleration is zero...
 

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