Finding the applied force with theta, A, M, and Mu as givens?

AI Thread Summary
To find the applied force needed to accelerate a 2kg block at 1.1 m/s² at an angle of 25 degrees above the horizontal with a coefficient of kinetic friction of 0.3, the equations of motion and friction must be applied. The net force in the y-direction is calculated using the normal force (Fn), applied force (Fav), and weight (W). The frictional force (Ff) is determined by multiplying the coefficient of friction (μ) by the normal force. The user is struggling to incorporate the coefficient of friction and subscripts into their calculations. Clear guidance on using symbols and formatting in the discussion is provided to assist with the calculations.
Potatoe
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Homework Statement


What must be the applied force (25 degrees above the horizontal) in order to accelerate a block at 1.1 m/s^2, if the mass is 2kg and the coefficient of kinetic friction is .3?

Homework Equations


F(net y)=Fn + Fav - W
Ff = μ x Fn
F(net x)=Fah-Ff

The Attempt at a Solution


I've substitued the variables in and gotten these:
2(1.1) - xsin25 + 2(9.81) = Fn
Ff = .3Fn
2(1.1) = xcos25 - Fn

How do I find Fn?
 
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Sorry, I'm not sure how to insert mu as a symbol or do subscripts
 
Potatoe said:
Sorry, I'm not sure how to insert mu as a symbol or do subscripts

Just copy and paste this symbol:

μ

where you need it, and to do subscripts or superscripts, just look at the toolbar at the top of the thread entry and you'll se a bold X with blue 2 subscript/superscript. It's near to big blue eye symbol and the TV icon!
 
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