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Homework Statement
Hi. My task is to find the Force F, so that velocity is constant.
I know that the velocity is constant, therefore the sum of all forces must be zero!
On the image I have used vector decomposition (the black lines). The orange ones are the vectors.
I know that the angle is 36,9 degrees. (the one marked with a half a circle).
I also know that the friction number is 0,25.
Explanation of the attached image:
G = Gravity
N = Normal Force
Ff = Friction
F = The force I must find
Homework Equations
[tex]Gx=0,6mg[/tex]
[tex]Gy=0,8mg[/tex]
[tex]Fx=0,8ma[/tex]
[tex]Fy=0,6ma[/tex]
[tex]\mu \; =\; 0.25[/tex]
[tex]N = Gy + Fy[/tex]
The Attempt at a Solution
I have tried to find N by using this formula:
[tex]\mu \; =\; \frac{Ff}{N}[/tex]
Then I thought that I could find Fy and Fx and use Phytagoras to find F. But my idea doesn't work (at least not the way I did it).
I don't know how to think to solve this one... The mass is unknown and frustrates me alot. Can anyone give me a tip?
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