Finding Minimum Force Applied to Keep Objects Stationary?

AI Thread Summary
To keep the crate stationary on the incline, the minimum force F must counteract the forces acting on it, including gravitational force and friction. The coefficient of static friction is .300, and the mass of the crate is 3.00 kg with an incline angle of 35°. The equation to consider is mgsinθ - μsmgcosθ + F = 0, where F represents the additional frictional force caused by the applied force. Understanding the relationship between F and the frictional force is crucial for solving the problem. The discussion clarifies that the focus should be on how F affects the friction rather than determining F alone.
morgane28v
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The coefficient of static friction between the crate m1=3.00kg and the incline with θ=35° shown in the figure below is .300. What minimum force F must be applied to the crate perpendicular to the incline to prevent the crate from sliding down the incline?


mgsinθ
μsmgcosθ
f=ma

I don't quite get how the applied force fits into the equation. mgsinθ-μsmgcosθ+F=0?
 

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Your equation is almost right. You are not interested so much in F itself but the additional frictional force caused by F.
 
Okay thank you I got it!
 
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