Yes! Calculating Friction Coefficient

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The calculations for the friction coefficient involve determining the force of gravity (Fg), net force (Fnet), and the forces acting on the object (Fax and Fay). The final friction coefficient is calculated as 10 divided by the normal force (Fn), which is derived from the gravitational force minus the vertical component of the applied force. There are concerns about the accuracy of the significant figures used in the calculations, suggesting they should be rounded to three. Additionally, clarification is needed regarding the expression "Fax = Fax leftward - Fax rightward." Overall, the calculations appear correct with some minor adjustments needed for precision.
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Homework Statement
A 30kg object is being pulled across a horizontal surface. The acceleration is 1.2 m/s2. The object is being pulled by a handle that is at 25 degrees. Friction force is 10 N. What forces can we find?
Relevant Equations
Fg = m * g
Fnet = m * a
Fa = Fax / cos(angle)
Fax = Fax leftward - Fax rightward
Fay = Fa * sin(angle)
Fg = m * g:
Fg = 30 * 9.8 = 294 N

Fnet = m * a:
Fnet = 30 * 1.2 = 36 N

Fax = Fnet + Ff:
Fax = 36 + 10 = 46

Fa = Fax / cos(angle):
Fa = 46 / cos(25) = 50.75

Fay = Fa * sin(angle):
Fay = 50.76 * sin(25) = 21.45

Fn = Fg - Fay:
Fn = 294 - 21.45 = 272.55

Ff = mu kinetic * Fn, solving for coefficient:
Coefficient of friction = 10 / 272.55 = .035Does this look correct?
 
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Making assumptions about how you are defining your variables, it all looks ok, except "Fax = Fax leftward - Fax rightward". What did you mean by that?
Your answers show too many significant figures, given the precision of the provided numbers. Round to at most three.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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